Developmental robotics: a survey
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paper_title: Robots as cognitive tools

paper_content:

Artificial intelligence is by its very nature synthetic, its motto is “Understanding by building”. In the early days of artificial intelligence the focus was on abstract thinking and problem solving. These phenomena could be naturally mapped onto algorithms, which is why originally AI was considered to be part of computer science and the tool was computer programming. Over time, it turned out that this view was too limited to understand natural forms of intelligence and that embodiment must be taken into account. As a consequence the focus changed to systems that are able to autonomously interact with their environment and the main tool became the robot. The “developmental robotics” approach incorporates the major implications of embodiment with regard to what has been and can potentially be learned about human cognition by employing robots as cognitive tools. The use of “robots as cognitive tools” is illustrated in a number of case studies by discussing the major implications of embodiment, which are of a dynamical and information theoretic nature.
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paper_title: Synthetic neural modeling: the 'Darwin' series of recognition automata

paper_content:

The authors describe how the theory of neuronal group selection (TNGS) can form the basis for an approach to computer modeling of the nervous system. Three examples of synthetic neural modeling are discussed. Darwin I was designed to examine the process of pattern recognition and some general factors relating to degeneracy and amplification in selective systems. Darwin II introduced recognition units with some of the properties of neuronal groups, connected in reentrant networks to permit exploration of aspects of the recognition process leading to categorization, generalization, and associative memory. Darwin III is a behaving automation whose behavior is not programmed but results from its encounter with events in its world under constraints of neuronal and synaptic selection. The oculomotor, reaching, touch, and categorization subsystems of the Darwin-III system are discussed. Darwin III is compared to models based on neurobiology, models based on artificial intelligence, and connectionist models. >
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paper_title: An Autonomous Agent Navigating with a Polarized Light Compass

paper_content:

One of the fundamental abilities required in autonomous agents is homing. Natural agents—for instance, desert ants—solve the homing problem mainly by using path integration within an egocentric frame of reference. When employing such a mechanism, compass information for determining direction is necessary, and the precision of the compass will have a crucial effect on the precision of homing. For deriving compass information, certain insects use the pattern of polarized light in the sky that arises due to scattering of sunlight in the atmosphere (polarized light compass). The analysis of skylight polarization is mediated by specialized photoreceptors and neurons in the visual system. Inspired by the insect's polarized light compass, we have constructed a polarization compass that was employed successfully on the mobile robot Sahabot. Three models for extracting compass information from the polarization pattern of the sky were tested. In this article, we describe the navigation system and report results of ...
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paper_title: Cognitive developmental robotics as a new paradigm for the design of humanoid robots

paper_content:

This paper proposes cognitive developmental robotics(CDR) as a new principle for the design of humanoid robots. This principle may provide ways of understanding human beings that go beyond the current level of explanation found in the natural and social sciences. Furthermore, a methodological emphasis on humanoid robots in the design of artificial creatures holds promise because they have many degrees of freedom and sense modalities and, thus, must face the challenges of scalability that are often side-stepped in simpler domains. We examine the potential of this new principle as well as issues that are likely to be important to CDR in the future. © 2001 Elsevier Science B.V. All rights reserved.
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paper_title: Alternative essences of intelligence

paper_content:

We present a novel methodology for building humanlike artificially intelligent systems. We take as a model the only existing systems which are universally accepted as intelligent: humans. We emphasize building intelligent systems which are not masters of a single domain, but, like humans, are adept at performing a variety of complex tasks in the real world. Using evidence from cognitive science and neuroscience, we suggest four alternative essences of intelligence to those held by classical AI. These are the parallel themes of development, social interaction, embodiment, and integration. Following a methodology based on these themes, we have built a physical humanoid robot. In this paper we present our methodology and the insights it affords for facilitating learning, simplifying the computation underlying rich behavior, and building systems that can scale to more complex tasks in more challenging environments.
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paper_title: Vehicles, Experiments in Synthetic Psychology

paper_content:

These imaginative thought experiments are the inventions of one of the world's eminent brain researchers. They are "vehicles," a series of hypothetical, self-operating machines that exhibit increasingly intricate if not always successful or civilized "behavior." Each of the vehicles in the series incorporates the essential features of all the earlier models and along the way they come to embody aggression, love, logic, manifestations of foresight, concept formation, creative thinking, personality, and free will. In a section of extensive biological notes, Braitenberg locates many elements of his fantasy in current brain research.
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paper_title: Synthetic neural modeling: the 'Darwin' series of recognition automata

paper_content:

The authors describe how the theory of neuronal group selection (TNGS) can form the basis for an approach to computer modeling of the nervous system. Three examples of synthetic neural modeling are discussed. Darwin I was designed to examine the process of pattern recognition and some general factors relating to degeneracy and amplification in selective systems. Darwin II introduced recognition units with some of the properties of neuronal groups, connected in reentrant networks to permit exploration of aspects of the recognition process leading to categorization, generalization, and associative memory. Darwin III is a behaving automation whose behavior is not programmed but results from its encounter with events in its world under constraints of neuronal and synaptic selection. The oculomotor, reaching, touch, and categorization subsystems of the Darwin-III system are discussed. Darwin III is compared to models based on neurobiology, models based on artificial intelligence, and connectionist models. >
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paper_title: Knowledge of language : its nature, origin, and use

paper_content:

Why do we know so much more than we have evidence for in certain areas, and so much less in others? In tackling these questions--Plato's and Orwell's problem--Chomsky again demonstrates his unequalled capacity to integrate vast amounts of material...A clear introduction to current thinking on grammatical theory. David W. Lightfoot, University of Maryland I feel that it is his most persuasive defense of the idea that the study of linguistic structure provides insight into the human mind. Frederick J. Newmeyer, University of Washington This is an excellent contribution to the philosophy of language and the philosophy of mind...The best available introduction to Chomsky's current ideas on syntax made accessible to the non-specialist. Julius M. Moravcsik, Stanford Unviersity
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paper_title: A Dynamic Systems Approach to the Development of Cognition and Action

paper_content:

A Dynamic Systems Approach to the Development of Cognition and Action presents a comprehensive and detailed theory of early human development based on the principles of dynamic systems theory. Beginning with their own research in motor, perceptual, and cognitive development, Thelen and Smith raise fundamental questions about prevailing assumptions in the field. They propose a new theory of the development of cognition and action, unifying recent advances in dynamic systems theory with current research in neuroscience and neural development. In particular, they show how by processes of exploration and selection, multimodal experiences form the bases for self-organizing perception-action categories. Thelen and Smith offer a radical alternative to current cognitive theory, both in their emphasis on dynamic representation and in their focus on processes of change. Among the first attempt to apply complexity theory to psychology, they suggest reinterpretations of several classic issues in early cognitive development. The book is divided into three sections. The first discusses the nature of developmental processes in general terms, the second covers dynamic principles in process and mechanism, and the third looks at how a dynamic theory can be applied to enduring puzzles of development. Cognitive Psychology series
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paper_title: Action recognition in the premotor cortex.

paper_content:

We recorded electrical activity from 532 neurons in the rostral part of inferior area 6 (area F5) of two macaque monkeys. Previous data had shown that neurons of this area discharge during goal-directed hand and mouth movements. We describe here the properties of a newly discovered set of F5 neurons (‘mirror neurons’, n = 92) all of which became active both when the monkey performed a given action and when it observed a similar action performed by the experimenter. Mirror neurons, in order to be visually triggered, required an interaction between the agent of the action and the object of it. The sight of the agent alone or of the object alone (three-dimensional objects, food) were ineffective. Hand and the mouth were by far the most effective agents. The actions most represented among those activating mirror neurons were grasping, manipulating and placing. In most mirror neurons (92%) there was a clear relation between the visual action they responded to and the motor response they coded. In ∼30% of mirror neurons the congruence was very strict and the effective observed and executed actions corresponded both in terms of general action (e.g. grasping) and in terms of the way in which that action was executed (e.g. precision grip). We conclude by proposing that mirror neurons form a system for matching observation and execution of motor actions. We discuss the possible role of this system in action recognition and, given the proposed homology between F5 and human Brocca’s region, we posit that a matching system, similar to that of mirror neurons exists in humans and could be involved in recognition of actions as well as phonetic gestures.
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paper_title: From perception to action: the right direction?

paper_content:

The underlying hypothesis of this paper is that there is no linear sequence leading from "perception to action" as the title of the conference suggests but that there is a continuous ongoing co-ordination. Rather the title should be interpreted as a design heuristic: instead of starting with "perception" we should start with "action". This perspective prevents us from overdesign and lends to "ecologically balanced systems".
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paper_title: Intelligence without Representation

paper_content:

Brooks, R.A., Intelligence without representation, Artificial Intelligence 47 (1991) 139159. Artificial intelligence research has foundered on the issue of representation. When intelligence is approached in an incremental manner, with strict reliance on interfacing to the real world through perception and action, reliance on representation disappears. In this paper we outline our approach to incrementally building complete intelligent Creatures. The fundamental decomposition of the intelligent system is not into independent information processing units which must interface with each other via representations. Instead, the intelligent system is decomposed into independent and parallel activity producers which all interface directly to the world through perception and action, rather than interface to each other particularly much. The notions of central and peripheral systems evaporateeverything is both central and peripheral. Based on these principles we have built a very successful series of mobile robots which operate without supervision as Creatures in standard office environments.
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paper_title: Language within our grasp

paper_content:

Abstract In monkeys, the rostral part of ventral premotor cortex (area F5) contains neurons that discharge, both when the monkey grasps or manipulates objects and when it observes the experimenter making similar actions. These neurons (mirror neurons) appear to represent a system that matches observed events to similar, internally generated actions, and in this way forms a link between the observer and the actor. Transcranial magnetic stimulation and positron emission tomography (PET) experiments suggest that a mirror system for gesture recognition also exists in humans and includes Broca's area. We propose here that such an observation/execution matching system provides a necessary bridge from `doing' to `communicating', as the link between actor and observer becomes a link between the sender and the receiver of each message.
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paper_title: Understanding motor events: a neurophysiological study

paper_content:

Neurons of the rostral part of inferior premotor cortex of the monkey discharge during goal-directed hand movements such as grasping, holding, and tearing. We report here that many of these neurons become active also when the monkey observes specific, meaningful hand movements performed by the experimenters. The effective experimenters' movements include among others placing or retrieving a piece of food from a table, grasping food from another experimenter's hand, and manipulating objects. There is always a clear link between the effective observed movement and that executed by the monkey and, often, only movements of the experimenter identical to those controlled by a given neuron are able to activate it. These findings indicate that premotor neurons can retrieve movements not only on the basis of stimulus characteristics, as previously described, but also on the basis of the meaning of the observed actions.
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paper_title: Unified Theories of Cognition

paper_content:

Introduction The Nature of Theories What Are Unified Theories of Cognition? Is Psychology Ready for Unified Theories? The Task of the Book Foundations of Cognitive Science Behaving Systems Knowledge Systems Representation Machines and Computation Symbols Architectures Intelligence Search and Problem Spaces Preparation and Deliberation Summary Human Cognitive Architecture The Human Is a Symbol System System Levels The Time Scale of Human Action The Biological Band The Neural Circuit Level The Real-Time Constraint on Cognition The Cognitive Band The Level of Simple Operations The First Level of Composed Operations The Intendedly Rational Band Higher Bands: Social, Historical, and Evolutionary Summary Symbolic Processing for Intelligence The Central Architecture for Performance Chunking The Total Cognitive System RI-Soar: Knowledge-Intensive and Knowledge-Lean Operation Designer-Soar: Difficult Intellectual Tasks Soar as an Intelligent System Mapping Soar onto Human Cognition Soar and the Shape of Human Cognition Summary Immediate Behavior The Scientific Role of Immediate-Response Data Methodological Preliminaries Functional Analysis of Immediate Responses The Simplest Response Task (SRI) The Two-Choice Response Task (2CRT) Stimulus-Response Compatibility (SRC) Discussion of the Three Analyses Item Recognition Typing Summary Memory, Learning, and Skill The Memory and Learning Hypothesis of Soar The Soar Qualitative Theory of Learning The Distinction between Episodic and Semantic Memory Data Chunking Skill Acquisition Short-Term Memory (STM) Summary Intendedly Rational Behavior Ciyptarithmetic Syllogisms Sentence Verification Summary Along the Frontiers Language Development The Biological Band The Social Band The Role of Applications How to Move toward Unified Theories of Cognition References Name Index Subject Index
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paper_title: Computation and Cognition: Toward a Foundation for Cognitive Science

paper_content:

The question, "What is Cognitive Science?" is often asked but seldom answered to anyone's satisfaction. Until now, most of the answers have come from the new breed of philosophers of mind. This book, however, is written by a distinguished psychologist and computer scientist who is well-known for his work on the conceptual foundations of cognitive science, and especially for his research on mental imagery, representation, and perception. In Computation and Cognition, Pylyshyn argues that computation must not be viewed as just a convenient metaphor for mental activity, but as a literal empirical hypothesis. Such a view must face a number of serious challenges. For example, it must address the question of "strong equivalents" of processes, and must empirically distinguish between phenomena which reveal what knowledge the organism has, phenomena which reveal properties of the biologically determined "functional architecture" of the mind. The principles and ideas Pylyshyn develops are applied to a number of contentious areas of cognitive science, including theories of vision and mental imagery. In illuminating such timely theoretical problems, he draws on insights from psychology, theoretical computer science, artificial intelligence, and psychology of mind. A Bradford Book
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paper_title: Functional Movement Development Across the Life Span

paper_content:

UNIT ONE: DEFINITION OF FUNCTIONAL MOVEMENT Chapter 1 - Functional Independence: A Lifelong Goal Chapter 2 - Theories Affecting Development Chapter 3 - Motor Development and Motor Control Chapter 4 - Motor Learning and Motor Control Chapter 5 - Evaluation of Function UNIT TWO: BODY SYSTEMS CONTRIBUTING TO FUNCTIONAL MOVEMENT Chapter 6 - Skeletal System Changes Chapter 7 - Muscular System Changes Chapter 8 - Cardiovascular and Pulmonary System Changes Chapter 9 - Nervous System Changes Chapter 10 - Sensory System Changes UNIT THREE: FUNCTIONAL MOVEMENT OUTCOMES Chapter 11 - Vital Functions Chapter 12 - Posture and Balance Chapter 13 - Locomotion Chapter 14 - Prehension Chapter 15 - Health and Fitness
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paper_title: A Dynamic Systems Approach to the Development of Cognition and Action

paper_content:

A Dynamic Systems Approach to the Development of Cognition and Action presents a comprehensive and detailed theory of early human development based on the principles of dynamic systems theory. Beginning with their own research in motor, perceptual, and cognitive development, Thelen and Smith raise fundamental questions about prevailing assumptions in the field. They propose a new theory of the development of cognition and action, unifying recent advances in dynamic systems theory with current research in neuroscience and neural development. In particular, they show how by processes of exploration and selection, multimodal experiences form the bases for self-organizing perception-action categories. Thelen and Smith offer a radical alternative to current cognitive theory, both in their emphasis on dynamic representation and in their focus on processes of change. Among the first attempt to apply complexity theory to psychology, they suggest reinterpretations of several classic issues in early cognitive development. The book is divided into three sections. The first discusses the nature of developmental processes in general terms, the second covers dynamic principles in process and mechanism, and the third looks at how a dynamic theory can be applied to enduring puzzles of development. Cognitive Psychology series
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paper_title: Learning and development in neural networks: the importance of starting small

paper_content:

It is a striking fact that in humans the greatest learnmg occurs precisely at that point in time - childhood - when the most dramatic maturational changes also occur. This report describes possible synergistic interactions between maturational change and the ability to learn a complex domain (language), as investigated in connectionist networks. The networks are trained to process complex sentences involving relative clauses, number agreement, and several types of verb argument structure. Training fails in the case of networks which are fully formed and ‘adultlike’ in their capacity. Training succeeds only when networks begin with limited working memory and gradually ‘mature’ to the adult state. This result suggests that rather than being a limitation, developmental restrictions on resources may constitute a necessary prerequisite for mastering certain complex domains. Specifically, successful learning may depend on starting small.
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paper_title: Emergent Forms: Origins and Early Development of Human Action and Perception

paper_content:

Part I: Ecological and Dynamical Foundations 1. Fundamental Issues and Perspectives in the Development of Action 2. From Bernstein and von Holst to Dynamical Systems Complexity 3. Ecological Foundations 4. The Components of Action Systems: Subsystems and Their Interaction Part II: Self-Organization and Selection as the Basis for the Assembly of Action Systems 5. Spontaneous Pattern Formation 6. Selection and the Emergence of Specialized Functions 7. The Ontogeny of Action Systems: A Theory Part III: The Action Systems 8. Basic Orienting 9. Appetition 10. Locomotion 11. The Performatory Action System: Manual Activity 12. The Expressive Action System 13. Directions
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paper_title: A Dynamic Systems Approach to the Development of Cognition and Action

paper_content:

A Dynamic Systems Approach to the Development of Cognition and Action presents a comprehensive and detailed theory of early human development based on the principles of dynamic systems theory. Beginning with their own research in motor, perceptual, and cognitive development, Thelen and Smith raise fundamental questions about prevailing assumptions in the field. They propose a new theory of the development of cognition and action, unifying recent advances in dynamic systems theory with current research in neuroscience and neural development. In particular, they show how by processes of exploration and selection, multimodal experiences form the bases for self-organizing perception-action categories. Thelen and Smith offer a radical alternative to current cognitive theory, both in their emphasis on dynamic representation and in their focus on processes of change. Among the first attempt to apply complexity theory to psychology, they suggest reinterpretations of several classic issues in early cognitive development. The book is divided into three sections. The first discusses the nature of developmental processes in general terms, the second covers dynamic principles in process and mechanism, and the third looks at how a dynamic theory can be applied to enduring puzzles of development. Cognitive Psychology series
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paper_title: Solving Bernstein's Problem: A Proposal for the Development of Coordinated Movement by Selection

paper_content:

In recent years, many established concepts in the theory of human motor development have undergone profound change, and our knowledge has increased greatly. Nevertheless, some outstanding problems remain unsolved. A central problem concerns the redundancy of effective movements, first pointed out by N. A. Bernstein. The human motor system is mechanically complex and can make use of large number of degrees of freedom. The controlled operation of such a system requires a reduction of mechanical redundancy, effectively by reducing the number of degrees of freedom. More recent work has shown that this problem is hard to solve explicitly by computing solutions to the equations of motion of the system. Equally challenging to traditional computational approaches is the fact the motor systems show remarkable adaptability and flexibility in the presence of changing biomechanical properties of motor organs during development and when faced with different environmental conditions or tasks. Solutions to these problems would have a large impact on a variety of issues in child development. In this article, we stress the importance of the somatic selection of neuronal groups in maps for the progressive transformation of a primary movement repertoire into a set of motor synergies and adaptive action patterns. We present results from computer simulations of a simple motor system that works according to such selectional principles. This approach suggests a provisional solution to Bernstein's problem and provides new parameters to guide experimental approaches to the development of sensorimotor coordination.
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paper_title: Learning and development in neural networks: the importance of starting small

paper_content:

It is a striking fact that in humans the greatest learnmg occurs precisely at that point in time - childhood - when the most dramatic maturational changes also occur. This report describes possible synergistic interactions between maturational change and the ability to learn a complex domain (language), as investigated in connectionist networks. The networks are trained to process complex sentences involving relative clauses, number agreement, and several types of verb argument structure. Training fails in the case of networks which are fully formed and ‘adultlike’ in their capacity. Training succeeds only when networks begin with limited working memory and gradually ‘mature’ to the adult state. This result suggests that rather than being a limitation, developmental restrictions on resources may constitute a necessary prerequisite for mastering certain complex domains. Specifically, successful learning may depend on starting small.
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paper_title: Four-Month-Old Infants Prefer to Listen to Motherese"

paper_content:

The speech register used by adults with infants and young children, known as motherese, is linguistically simplified and characterized by high pitch and exaggerated intonation. This study investigated infant selective listening to motherese speech. The hypothesis tested was that infants would choose to listen more often to motherese when given the choice between a variety of natural infant-directed and adult-directed speech samples spoken by four women unfamiliar to the subjects. Forty-eight 4-month-old infants were tested in an operant auditory preference procedure. Infants showed a significant listening preference for the motherese speech register.
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paper_title: Sensitive periods in development: Structural characteristics and causal interpretations.

paper_content:

The presence or absence of a particular experience at a particular time in the life cycle may exert an extraordinary and dramatic influence over structure or function well beyond that point in development. Such sensitive periods are thought to be widespread in animal and in human neurobiology and psychology. A comprehensive treatment of the sensitive period needs minimally to include information about its structural characteristics as well as an interpretation of its causes, including why the sensitive period arises in terms of the natural history of the species and how the sensitive period is regulated in terms of physical, physiological, and psychological processes. This article provides a framework for research and theory concerning specific sensitive periods and the sensitive period generally conceived. The framework delimits four sets of parameters, which encompass 14 structural characteristics that define sensitive periods, and two levels of causal interpretation that guide research and theory into sensitive periods however they may be manifested.
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paper_title: Experiential Canalization of Behavioral Development: Theory

paper_content:

Waddington's (1942) notion of canalization has been widely invoked in developmental psychology to conceptualize species-typical regularities in behavioral development as genetically determined. In contrast, a developmental systems view, such as the one described in the present article, sees the genes as only one component in a hierarchy of influences, all of which contribute to canalize behavioral development. A key issue is that genetic activity does not by itself produce finished traits; differentiation occurs as a consequence of events above as well as below the cellular level, necessarily involving factors in addition to genetic influences to canalize behavioral development. In exploring the possible experiential canalization of development, it was found that the mallard duck embryo's contact call plays a canalizing role in species-speci fic perceptual development {Gottlieb, 1991). Thus, normally occurring experience, in concert with genetic and other activities, can canalize behavioral development. The concept of canalization has been utilized in several different ways in the psychological literature. Canalization was originally put forward by Holt (1931) to call attention to prenatal conditioning as a factor in narrowing down the initially diffuse or random nature of motor activity in the embryo or fetus. Holt saw the motor activity of the fetus and the infant as becoming organized through spatial and temporal contiguity learning that narrowed down originally diffuse neural pathways to a definite neural reflex arc. Thus, for Holt, canalization referred to the development of specific sensorimotor pathways out of an original multiplicity of such pathways; it was a label to capture the developmental-behavioral phenomenon of progression from diffuse to ordered or organized motor activity, with contiguity conditioning as the experiential mechanism whereby organized motor activity was achieved. Although Holt's concept of neural reflex circles to account for the development of grasping in the fetus and infant was an ingenious example of his point of view, it has remained an entirely speculative theoretical solution of primarily historical interest. Subsequent empirical studies in behavioral embryology have kept open the possibility that motor movements in the embryo and fetus of some species are patterned from the start, whereas in other species they appear to be random (see reviews in Gottlieb, 1970; Hamburger, 1973; Oppenheim, 1974).
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paper_title: Imitation of facial and manual gestures by human neonates.

paper_content:

Infants between 12 and 21 days of age can imitate both facial and manual gestures; this behavior cannot be explained in terms of either conditioning or innate releasing mechanisms. Such imitation implies that human neonates can equate their own unseen behaviors with gestures they see others perform.
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paper_title: Self-organized control of bipedal locomotion by neural oscillators in unpredictable environment

paper_content:

A new principle of sensorimotor control of legged locomotion in an unpredictable environment is proposed on the basis of neurophysiological knowledge and a theory of nonlinear dynamics. Stable and flexible locomotion is realized as a global limit cycle generated by a global entrainment between the rhythmic activities of a nervous system composed of coupled neural oscillators and the rhythmic movements of a musculo-skeletal system including interaction with its environment. Coordinated movements are generated not by slaving to an explicit representation of the precise trajectories of the movement of each part but by dynamic interactions among the nervous system, the musculo-skeletal system and the environment. The performance of a bipedal model based on the above principle was investigated by computer simulation. Walking movements stable to mechanical perturbations and to environmental changes were obtained. Moreover, the model generated not only the walking movement but also the running movement by changing a single parameter nonspecific to the movement. The transitions between the gait patterns occurred with hysteresis.
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paper_title: What minds have in common is space: Spatial mechanisms serving joint visual attention in infancy

paper_content:

A series of experiments is reported which show that three successive mechanisms are involved in the first 18 months of life in ‘looking where someone else is looking’. The earliest ‘ecological’ mechanism enables the infant to detect the direction of the adult's visual gaze within the baby's visual field but the mother's signal alone does not allow the precise localization of the target. Joint attention to the same physical object also depends on the intrinsic, attention-capturing properties of the object in the environment. By about 12 months, we have evidence for presence of a new ‘geometric’ mechanism. The infant extrapolates from the orientation of the mother's head and eyes, the intersection of the mother's line of sight within a relatively precise zone of the infant's own visual space. A third ‘representational’ mechanism emerges between 12 and 18 months, with an extension of joint reference to places outside the infant's visual field. ::: ::: None of these mechanisms require the infant to have a theory that others have minds; rather the perceptual systems of different observers ‘meet’ in encountering the same objects and events in the world. Such a ‘realist’ basis for interpersonal knowledge may offer an alternative starting point for development of intrapersonal knowledge, rather than the view that mental events can only be known by construction of a theory.
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paper_title: The imitative mind: Development, evolution, and brain bases

paper_content:

Part I. Introduction and Overview: 1. An interdisciplinary introduction to the imitative mind and brain Wolfgang Prinz and Andrew N. Meltzoff Part II. Developmental and Evolutionary Approaches to Imitation: 2. Building blocks for a developmental theory of imitation Andrew N. Meltzoff 3. Imitation and imitation recognition: functional use in preverbal infants and nonverbal children with autism Jacqueline Nadel 4. Self-awareness, other-awareness, and secondary representation Jens B. Asendorpf 5. Notes on individual differences and the assumed elusiveness of neonatal imitation Mikael Heimann 6. Ego function of early imitation Philippe Rochat 7. The imitator's representation of the imitated: ape and child A. Whiten 8. Seeing actions as hierarchically organised structures: great ape manual skills Richard W. Byrne Part III. Cognitive Approaches to Imitation, Body Scheme, and Perception-action Coding: 9. Experimental approaches to imitation Wolfgang Prinz 10. Imitation: common mechanisms in the observation and execution of finger and mouth movements Harold Bekkering 11. Goal-directed imitation Merideth Gattis, Harold Bekkering and Andreas Wolschlager 12. Visuomotor couplings in object-orientated and imitative actions Stefan Vogt 13. On bodies and events Barbara Tversky, Julie Bauer Morrison and Jeff Zacks 14. What is the body schema? Catherine L. Reed Part IV. Neuroscience Underpinnings of Imitation and Apraxia: 15. From mirror neurons to imitation: facts and speculations Giacomo Rizzolatti, Luciano Fadiga, Leonardo Fogassi and Vittorio Gallese 16. Cell populations in the banks of the superior temporal sulcus of the macaque and imitation T. Jellema, C. I. Baker, M. W. Oram and D. I. Perrett 17. Is there such a thing as a functional equivalence between imagined, observed, and executed action? Jean Decety 18. The role of imitation in body ownership and mental growth Marcel Kinsbourne 19. Imitation, apraxia, and hemisphere dominance Georg Goldenberg and Joachim Hermsdorfer.
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paper_title: Emergent Forms: Origins and Early Development of Human Action and Perception

paper_content:

Part I: Ecological and Dynamical Foundations 1. Fundamental Issues and Perspectives in the Development of Action 2. From Bernstein and von Holst to Dynamical Systems Complexity 3. Ecological Foundations 4. The Components of Action Systems: Subsystems and Their Interaction Part II: Self-Organization and Selection as the Basis for the Assembly of Action Systems 5. Spontaneous Pattern Formation 6. Selection and the Emergence of Specialized Functions 7. The Ontogeny of Action Systems: A Theory Part III: The Action Systems 8. Basic Orienting 9. Appetition 10. Locomotion 11. The Performatory Action System: Manual Activity 12. The Expressive Action System 13. Directions
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paper_title: Limitations on input as a basis for neural organization and perceptual development: A preliminary theoretical statement

paper_content:

We propose an alternative to the conventional view that limitations on infant functioning are handicaps to be overcome. According to our view, limitations, particularly of the sensory systems, produce adaptive advantages for infants by facilitating perceptual organization. During embryogenesis, developmental rates of sensory systems are unequal so that onset of functioning is sequential. We argue that such differential onset results in relative independence among emerging systems, thereby reducing competition which helps regulate subsequent neurogenesis and functioning. In addition to prenatal effects, neonatal sensory limitations are discussed as a major source of perceptual organization. Limitations reduce the amount of information with which the infant must contend and promote temporal contiguity between multimodal attributes of a stimulus. Although we focus on human perceptual development, our view is a broadly based comparative one. Thus, other organisms have evolved means of restricting sensory input, and evidence is cited suggesting the importance of this reduced input in regulating normal perceptual development.
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paper_title: A Dynamic Systems Approach to the Development of Cognition and Action

paper_content:

A Dynamic Systems Approach to the Development of Cognition and Action presents a comprehensive and detailed theory of early human development based on the principles of dynamic systems theory. Beginning with their own research in motor, perceptual, and cognitive development, Thelen and Smith raise fundamental questions about prevailing assumptions in the field. They propose a new theory of the development of cognition and action, unifying recent advances in dynamic systems theory with current research in neuroscience and neural development. In particular, they show how by processes of exploration and selection, multimodal experiences form the bases for self-organizing perception-action categories. Thelen and Smith offer a radical alternative to current cognitive theory, both in their emphasis on dynamic representation and in their focus on processes of change. Among the first attempt to apply complexity theory to psychology, they suggest reinterpretations of several classic issues in early cognitive development. The book is divided into three sections. The first discusses the nature of developmental processes in general terms, the second covers dynamic principles in process and mechanism, and the third looks at how a dynamic theory can be applied to enduring puzzles of development. Cognitive Psychology series
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paper_title: Maturational Constraints on Language Learning

paper_content:

This paper suggests that there are constraints on learning required to explain the acquisition of language, in particular, mului ultonol constraints. First, empirical evidence for this daim is reviewed. The evidence from several studies of both first and second languoge acquisition suggests that normal language learning occurs only when exposure to the languoge begins early in life. With exposure beginning later in life, asymptotic performance in the language declines: the effects over oge of first exposure are approximately linear through childhood, with a flattening of the function in adulthood. These outcomes argue that some type of constraints ensuring successful languoge learning exist early in life, and weaken with increasing maturation. Second, two hypotheses are considered as to the nature of these maturational changes. One hypothesis is that constraints on learning particular to languoge acquisition undergo maturational decay. A second hypothesis, which is considered in more detail, suggests that language learning abilities decline because of the expansion of nonlinguisftc cognitive abilities.
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paper_title: Neural Darwinism: The Theory of Neuronal Group Selection

paper_content:

Somatic Selection * A Summary and Historical Introduction * Structure, Function, and Perception * Neuronal Group Selection Epigenetic Mechanisms * Developmental Bases of Diversity: The Primary Repertoire * Cellular Dynamics of Neural Maps * Evolution and Function of Distributed Systems * Synapses as Populations: The Bases of the Secondary Repertoire Global Functions * Action and Perception * Categorization and Memory * Selective Networks and Recognition Automata * Selection, Learning, and Behavior Conclusion * Summary, Predictions, and Implications
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paper_title: The adaptive nature of cognitive immaturity.

paper_content:

The prolonged cognitive immaturity characteristic of human youth is described as adaptive in and of itself. The adaptive nature of cognitive immaturity is examined in developmental research in the areas of metacognition, egocentricity, plasticity and the speed of information processing, and language acquisition. Some of the consequences of viewing children's immature cognition as adaptive for cognitive development and education are discussed.
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paper_title: Perceived self in infancy

paper_content:

Research is presented suggesting that an implicit sense of self is developing from birth, long before children begin to manifest explicit (conceptual) self-knowledge by the second year. Implicit self-knowledge in infancy is rooted in intermodal perception and action. Studies are reported showing that at least from 2 months of age, infants become increasingly systematic and deliberate in the exploration of their own body and the perceptual consequences of self-produced action. From such exploration, infants develop a sense of their own body as a differentiated entity, situated and agent in the environment. Based on recent empirical findings, the perceptual determinants of such implicit sense of self are discussed.
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paper_title: Imitation in Infancy

paper_content:

Preface: Immediate imitation rehabilitated at last George Butterworth and Jacqueline Nadel Part I. Imitation in Human Infancy: 1. Persons and representation: why infant imitation is important for theories of human development Andrew N. Meltzoff and M. Keith Moore 2. Development of early infant imitation to facial and vocal models Giannis Kugiumutzakis Part II. Imitation: Theoretical issues in phylogeny and ontogeny: 3. Neonatal imitation: existence, mechanisms, motives George Butterworth 4. Evolutionary foundations of imitation: social, cognitive and developmental aspects of imitative processes in non-human primates Kim Bard and Connie L. Russell Part III. Social motives for imitation in infancy: Imitation as a matching motive system between two brains Colwyn Trevarthen, Theano Kokkinaki and Gerald A. Fiamenghi Jr 6. Imitation as activity: its developmental aspect Ina Uzgiris Part IV. Imitation, communication and developmental psychopathology: 7. The evolving nature of imitation as a format for communication Jacqueline Nadel, Caroline Guirini, Anne Peze and Christine Rivet 8. Imitation and developmental disabilities Mickael Heimann and Eva Ullstadius 9. An examination of the imitation deficit in autism Sally J. Rogers.
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paper_title: Kicking, rocking, and waving: Contextual analysis of rhythmical stereotypies in normal human infants

paper_content:

Abstract I analysed the triggering contexts of over 14 000 bouts of rhythmical stereotypies of the legs, arms, and whole torso observed in 20 normal infants during their first year. Infant stereotypies were elicited by a wide variety of contexts including non-alert states, interactions with the caregiver and other persons, feeding situations, object interest, and kinaesthetic changes. The frequency of stereotypy in all contexts was a function of age. Non-alert states and interactions with the caregiver were disproportionately associated with leg and torso stereotypies. The relationship between these human stereotypies and the function and control of stereotyped behaviour in other species is discussed.
---
paper_title: Solving Bernstein's Problem: A Proposal for the Development of Coordinated Movement by Selection

paper_content:

In recent years, many established concepts in the theory of human motor development have undergone profound change, and our knowledge has increased greatly. Nevertheless, some outstanding problems remain unsolved. A central problem concerns the redundancy of effective movements, first pointed out by N. A. Bernstein. The human motor system is mechanically complex and can make use of large number of degrees of freedom. The controlled operation of such a system requires a reduction of mechanical redundancy, effectively by reducing the number of degrees of freedom. More recent work has shown that this problem is hard to solve explicitly by computing solutions to the equations of motion of the system. Equally challenging to traditional computational approaches is the fact the motor systems show remarkable adaptability and flexibility in the presence of changing biomechanical properties of motor organs during development and when faced with different environmental conditions or tasks. Solutions to these problems would have a large impact on a variety of issues in child development. In this article, we stress the importance of the somatic selection of neuronal groups in maps for the progressive transformation of a primary movement repertoire into a set of motor synergies and adaptive action patterns. We present results from computer simulations of a simple motor system that works according to such selectional principles. This approach suggests a provisional solution to Bernstein's problem and provides new parameters to guide experimental approaches to the development of sensorimotor coordination.
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paper_title: Free(z)ing Degrees of Freedom in Skill Acquisition

paper_content:

Abstract This study reports an empirical investigation into Bernstein's (1967) ideas that in the early stages of the acquisition of a movement skill the coordination problem is reduced by an initial freezing out of degrees of freedom, followed later in the learning process by the release of these degrees of freedom and their incorporation into a dynamic, controllable system. “Freezing” degrees of freedom was made operational both as a rigid fixation of individual degrees of freedom and as the formation of rigid couplings between multiple degrees of freedom. Five subjects practiced slalom-like ski movements on a ski apparatus for 7 consecutive days. Results showed that at the early phases of learning, the joint angles of the lower limbs and torso displayed little movement, as expressed by their standard deviations and ranges of angular motion, whereas joint couplings were high, as shown by the relatively high cross correlations between joint angles. Over practice, angular movement significantly increased i...
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paper_title: Visual factors in hitting and catching

paper_content:

To hit or catch an approaching ball, it is necessary to move a bat or hand to the right place at the right time. The performance of top sports players is remarkable: positional errors of less than 5 cm and temporal errors of less than 2 or 3 ms are reliably maintained. There are three schools of thought about how this is achieved. One holds that predictive visual information about where the ball will be at some future instance (when) is used to achieve the hit or catch. The second holds that the bat or hand is moved to the correct position by exploiting some relation between visual information and the required movement. The third focuses on the use of prior knowledge to supplement inadequate visual information. For a rigid spherical ball travelling at constant speed along or close to the line of sight, the retinal images contain both binocular and monocular correlates of the ball's instantaneous direction of motion in depth. Also, the retinal images contain both binocular and monocular information about t...
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paper_title: Mass, center of mass, and moment of inertia estimates for infant limb segments.

paper_content:

To quantify limb dynamics, accurate estimates are needed of anthropometric inertia parameters (mass, center-of-mass location, and moments of inertia). These estimates, however, are not available for human infants; therefore, the movement dynamics of infants have not been studied extensively. Here, regression equations for the masses, center-of-mass locations, and transverse moments of inertia of upper and lower limb segments (upper arm, forearm, and hand; thigh, leg, and foot) of 0.04 to 1.50 yr old infants are provided. A mathematical model of the human body was used to determine the anthropometric inertia parameters for upper limbs in 44 infants and for lower limbs in 70 infants. Stepwise linear regressions were used to fit the distributions of the anthropometric inertia parameters. The regression equations accounted for significant amounts of the variance (64-98%), and the R2-values compared favorably when our equations were cross-validated. Consequently, these regression equations can provide, for infants of similar ages, reasonable estimates of upper and lower limb anthropometric inertia parameters, suitable for equations of motion in the analysis of limb dynamics in human infants.
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paper_title: Neural control of human motor development

paper_content:

Abstract It has been possible to expand considerably our understanding of human motor development by making a detailed analysis of various types of movement and muscular activation patterns during different stages of development. Alterations in development subsequent to the appearance of brain lesions have enabled valuable information to be collected about the underlying neural mechanisms, in addition to new information concerning the pathophysiology of cerebral palsy. Studies on the development of the corticospinal system indicate that plastic changes can take place after perinatal brain damage.
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paper_title: Biomechanics and Developmental Neuromotor Control.

paper_content:

By applying the principles and methods of mechanics to the musculoskeletal system, new insights can be discovered about control of human limb dynamics both in adults and infants. Here, we first provide a basic primer about biomechanics--its historical context, terminology, and analytical techniques. Next we review research with animals and human adults that illustrates how limb dynamics provides a window for examining the physical mechanisms underlying neuromotor control. Finally, we elaborate on how our research group has adapted dynamics techniques to investigate how infants gain control of their limbs and learn to reach in the first year of life. Language: en
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paper_title: Emergent Forms: Origins and Early Development of Human Action and Perception

paper_content:

Part I: Ecological and Dynamical Foundations 1. Fundamental Issues and Perspectives in the Development of Action 2. From Bernstein and von Holst to Dynamical Systems Complexity 3. Ecological Foundations 4. The Components of Action Systems: Subsystems and Their Interaction Part II: Self-Organization and Selection as the Basis for the Assembly of Action Systems 5. Spontaneous Pattern Formation 6. Selection and the Emergence of Specialized Functions 7. The Ontogeny of Action Systems: A Theory Part III: The Action Systems 8. Basic Orienting 9. Appetition 10. Locomotion 11. The Performatory Action System: Manual Activity 12. The Expressive Action System 13. Directions
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paper_title: Catching balls: How to get the hand to the right place at the right time.

paper_content:

Information specifying the future passing distance of an approaching object is available (in units of object size) in the ratio of optical displacement velocity and optical expansion velocity. Despite empirical support for the assumption that object size can serve as a metric in the perception of passing distance, the present series of experiments reveals that in catching a ball subjects do not rely on such «point-predictive» information. The angle at which (real and simulated) balls approached the subject systematically affected verbal and manual estimates of future passing distance, as well as the kinematic characteristics of catching movements. To catch a ball, the actor uses momentary action-related information instead of spatiotemporal estimates. The hand velocity is geared to information specifying the currently required velocity
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paper_title: A unifying computational framework for motor control and social interaction

paper_content:

Recent empirical studies have implicated the use of the motor system during action observation, imitation and social interaction. In this paper, we explore the computational parallels between the processes that occur in motor control and in action observation, imitation, social interaction and theory of mind. In particular, we examine the extent to which motor commands acting on the body can be equated with communicative signals acting on other people and suggest that computational solutions for motor control may have been extended to the domain of social interaction.
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paper_title: Perspectives and problems in motor learning

paper_content:

Abstract Movement provides the only means we have to interact with both the world and other people. Such interactions can be hard-wired or learned through experience with the environment. Learning allows us to adapt to a changing physical environment as well as to novel conventions developed by society. Here we review motor learning from a computational perspective, exploring the need for motor learning, what is learned and how it is represented, and the mechanisms of learning. We relate these computational issues to empirical studies on motor learning in humans.
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paper_title: Exploration in the service of prospective control

paper_content:

Abstract We propose a sequential process of exploration that can account for perception-action coupling in infant locomotion. Each phase in the sequence is a process of obtaining progressively more information leading to a motor decision—exploration from a distance, exploration via direct contact, and exploration of alternative means. Quick glances and prolonged looking from afar serve to alert the perceiver to important changes in the terrain. Intentional touching and testing alternative ways to traverse an obstacle are only prompted when prior information indicates a potential threat to balance. We further propose that depth information is privileged because it can be detected from a distance more readily than other surface properties such as rigidity and friction. Studies of infants walking down slopes and across “hole/patch” transitions illustrate the important role of exploration in prospective control of locomotion.
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paper_title: Analysis of general movements of infants towards understanding of developmental principle for motor control

paper_content:

We focus on the spontaneous movements of young infants who have not yet acquired voluntary movements. Dynamical complexity and variability are characteristic points of the movements in the spine position, which are called general movements (GMs). We studied the GMs of 8 normal and 2 abnormal infants from 1 to 6 months old of age. Kinematic analysis of the trajectories of hands and feet using a nonlinear prediction method revealed that a u-shape change occurs around 2 months of age. The trajectories were very complex with no clear coordination among the limbs at the age of 1 and 3 months, while rhythmic movements were conspicuous at the age of 2 months. GMs of 2 abnormal infants with brain impairments showed a simply rhythmic pattern and a random pattern, respectively. The u-shape change in the GM of normal development and the loss of complexity of movements of brain damaged infants support the hypothesis that the neuromuscular system of newborns has nonlinear dynamics and that freezing and freeing degrees of freedom play an important role in motor development.
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paper_title: A Dynamic Systems Approach to the Development of Cognition and Action

paper_content:

A Dynamic Systems Approach to the Development of Cognition and Action presents a comprehensive and detailed theory of early human development based on the principles of dynamic systems theory. Beginning with their own research in motor, perceptual, and cognitive development, Thelen and Smith raise fundamental questions about prevailing assumptions in the field. They propose a new theory of the development of cognition and action, unifying recent advances in dynamic systems theory with current research in neuroscience and neural development. In particular, they show how by processes of exploration and selection, multimodal experiences form the bases for self-organizing perception-action categories. Thelen and Smith offer a radical alternative to current cognitive theory, both in their emphasis on dynamic representation and in their focus on processes of change. Among the first attempt to apply complexity theory to psychology, they suggest reinterpretations of several classic issues in early cognitive development. The book is divided into three sections. The first discusses the nature of developmental processes in general terms, the second covers dynamic principles in process and mechanism, and the third looks at how a dynamic theory can be applied to enduring puzzles of development. Cognitive Psychology series
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paper_title: Dimensional change in motor learning.

paper_content:

Bernstein (The Co-ordination and Regulation of Movements, Pergamon, London, 1967) outlined a theoretical framework for the degrees of freedom problem in motor control that included a 3-stage approach to the reorganization of the peripheral biomechanical degrees of freedom in motor learning and development. We propose that Bernstein's conception of change through the stages of learning is too narrow in its consideration of the degrees of freedom problem and the actual pathways of change evident in motor learning. It is shown that change in both the organization of the mechanical degrees of freedom and the dimension of the attractor dynamic organizing motor output can either increase or decrease, according to the confluence of constraints imposed on action. The central issue determining directional change in dimension is whether the dimensionality of the task relevant intrinsic dynamic needs to be increased or decreased to realize new task demands.
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paper_title: Developmental profiles of spontaneous movements in infants

paper_content:

Abstract Spontaneous movements were observed for 1-h sessions in each of 50 normal full-term infants aged from 2 weeks to 50 weeks in their own homes using videoanalysis. Movements were categorised according to the classifications of Thelen [17] and Hopkins and Prechtl [10]. Developmental profiles for the frequency of occurrence of the different types of movements were determined. These were found to be dependent on the posture and mobility ( P P P
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paper_title: Core knowledge.

paper_content:

Compex cognitive skills such as reading and calculation and complex cognitive achievements such as formal science and mathematics may depend on a set of building block systems that emerge early in human ontogeny and phylogeny. These core knowledge systems show characteristic limits of domain and task specificity: Each serves to represent a particular class of entities for a particular set of purposes. By combining representations from these systems, however, human cognition may achieve extraordinary flexibility. Studies of cognition in human infants and in nonhuman primates therefore may contribute to understanding unique features of human knowledge.
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paper_title: Object manipulation and exploration in 2- to 5-month-old infants

paper_content:

The early development of explorarory behavior was studied. One study documents changes in free exploration of infants aged from 2 to 5 months. Another compares 3- and 4-5 month-olds when manipulating and exploring an object in the light or in the dark (no visual control over exploration). The third study compares multimodal exploration in 3- and 4-month-olds when presented with two different objects varying in multiple properties. Results show that significant changes occur between 2 and 5 months, relative to spontaneous multimodal exploration of a novel object. Object exploration becomes increasingly multimodal. Bimanual coordination is first linked to the oral system, later reorganized in reference to vision when fingering emerges by 4 months. Manipulation in 3-montholds is shown to be object-dependent. Factors controlling early object manipulation and functional changes in manual action prior to 6 months of age are discussed. When young infants are in an alert and quiet state, they display behaviors that are "exploratory" in nature because they appear to be primarily oriented toward bringing sense organs into various relations with objects in the environment. Newborns show elements of reaching with arms and hands toward an object moving close to them (Hofsten, 1982). Young infants track objects moving in their field of view with both eyes and head (Bullinger, 1984). From birth, they orient their heads in the direction of a sound source (Clifton, Morrongiello, Kulig, & Dowd, 1981; Muir & Field, 1979) and appear to selectively orient (root) their mouths in the direction of a familiar odor (Macfarlane, 1975). Contrary to the view that babies are passive spectators bombarded with stimulation, these observations indicate that from the earliest age infants are actors and, in particular, explorers of their environment. From a theoretical point of view, it is relevant to approach early behavior as involving action systems with specific adaptative functions like communi
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paper_title: Learning to cruise: Bernstein's theory applied to skill acquisition during infancy

paper_content:

Abstract Cruising represents an important transition from quadrupedal to bipedal locomotion. While cruising, infants discover ways to control their trunks in upright. We predicted that the movement patterns infants demonstrated when learning to control the trunk in order to cruise and walk independently would reflect the process Bernstein [cf. N.B. Bernstein, The Coordination and Regulation of Movements, Pergamon Press, Oxford, England, 1967] proposed for adults' skill acquisition. In addition, we expected that infants would demonstrate a precursor poorly controlled exploratory phase, what we termed the “wobble phase”. We examined longitudinal changes in movement control of the thorax and pelvis from the onset of cruising through the onset of walking. Our findings suggest that learning to cruise involves an initial wobble phase followed by a gradual reduction in the wobble, or number of movement corrections. Finally a relative plateau period of control emerged with sporadic variability in the movement patterns of the thorax and pelvis. We suggest that the fact that infants did not show a phase in which they froze degrees of freedom was due to a lack of the minimum level of control one needs in order to do this. By the end of cruising, although functionally quite skillful, infants continued to demonstrate multiple and varied patterns of control. Infants limit the degrees of freedom just enough to successfully accomplish the task. We argue that variability remains due to: the minimal negative consequences of trunk inconsistency in this context given the available arm support; the trunk acts as a flexible interface for the, as yet, unstable coupling between the arms and legs; and the low number of constraints in relation to the multiple solutions that the task affords. Despite of the remaining variability, it appears that the control of the trunk acquired during cruising enables infants to shift into walking independently.
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paper_title: Self-perception and action in infancy

paper_content:

By 2–3 months, infants engage in exploration of their own body as it moves and acts in the environment. They babble and touch their own body, attracted and actively involved in investigating the rich intermodal redundancies, temporal contingencies, and spatial congruence of self-perception. Recent research is presented, which investigats the spatial and temporal determinants of self-perception and action infancy. This research shows that, in the course of the first weeks of life, infants develop an ability to detect intermodal invariants and regularities in their sensorimotor experience, which specify themselves as separate entities agent in the environment. Recent observations on the detection of intermodal invariants regarding self-produced leg movements and auditory feedback of sucking by young infants are reported. These observations demonstrate that, early in development and long before mirror self-recognition, infants develop a perceptual ability to specify themselves. It is tentatively proposed that young infants’ propensity to engage in self-perception and systematic exploration of the perceptual consequences of their own action plays an important role in the intermodal calibration of the body and is probably at the origin of an early sense of self: the ecological self.
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paper_title: Is the cerebellum a smith predictor

paper_content:

The motor system may use intemal predictive models of the motor apparatus to achieve better control than would be possible by negative feedback. Several theories have proposed that the cerebellum may form these predictive representations, In this article, we review these theories and try to unify them by reference to an engineering control model known as a Smith Pre dictor. We suggest that the cerebellum forms two types of internal model. One model is a forward predictive model of the motor apparatus (e.g. , limb and muscle), providing a rapid prediction of the sensory consequences of each movement. The second model is of the time delays in the control loop (due to receptor and effec- tor delays, axona) conductances, and cognitive processing de- lays). This model delays a copy of the rapid prediction so that it can be compared in temporal register with actual sensory feedback from the movement. The result of this comparison is used both to correct for errors in perf.ormance and as a training signal to learn the first model We discuss evidence that the cerebellum could form both of these models and suggest that the cerebellum may hold at least two separate Smith Predictors. One, in the lateral cerebellum, would predict the movement outcome in visual, ego- centric, or peripersonaJ coordinates. Another, in the intermediate cerebellum, would predict the consequences in motor coordinates. Generalization of the Smith Predictor theory is discussed in ) ight of cerebellar involvement in nonmotor control systems, including autonomic functions and cognition
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paper_title: Perceived self in infancy

paper_content:

Research is presented suggesting that an implicit sense of self is developing from birth, long before children begin to manifest explicit (conceptual) self-knowledge by the second year. Implicit self-knowledge in infancy is rooted in intermodal perception and action. Studies are reported showing that at least from 2 months of age, infants become increasingly systematic and deliberate in the exploration of their own body and the perceptual consequences of self-produced action. From such exploration, infants develop a sense of their own body as a differentiated entity, situated and agent in the environment. Based on recent empirical findings, the perceptual determinants of such implicit sense of self are discussed.
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paper_title: Understanding movement control in infants through the analysis of limb intersegmental dynamics

paper_content:

One important component in the understanding of the control of limb movements is the way in which the central nervous system accounts for joint forces and torques that may be generated not only by muscle actions but by gravity and by passive reactions related to the movements of limb segments. In this study, we asked how the neuromotor system of young infants controls a range of active and passive forces to produce a stereotypic, nonintentional movement. We specifically analyzed limb intersegmental dynamics in spontaneous, cyclic leg movements (kicking) of varying intensity in supine 3-month-old human infants. Using inverse dynamics, we calculated the contributions of active (muscular) and passive (motion-dependent and gravitational) torque "components at the hip, knee, and ankle joints from three-dimensional limb kinematics. To calculate joint torques, accurate estimates were needed of the limb's anthropometric parameters, which we determined using a model of the human body. Our analysis of limb interseg...
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paper_title: Kicking, rocking, and waving: Contextual analysis of rhythmical stereotypies in normal human infants

paper_content:

Abstract I analysed the triggering contexts of over 14 000 bouts of rhythmical stereotypies of the legs, arms, and whole torso observed in 20 normal infants during their first year. Infant stereotypies were elicited by a wide variety of contexts including non-alert states, interactions with the caregiver and other persons, feeding situations, object interest, and kinaesthetic changes. The frequency of stereotypy in all contexts was a function of age. Non-alert states and interactions with the caregiver were disproportionately associated with leg and torso stereotypies. The relationship between these human stereotypies and the function and control of stereotyped behaviour in other species is discussed.
---
paper_title: Explaining facial imitation: a theoretical model

paper_content:

A long-standing puzzle in developmental psychology is how infants imitate gestures they cannot see themselves perform (facial gestures). Two critical issues are: (a) the metric infants use to detect cross-modal equivalences in human acts and (b) the process by which they correct their imitative errors. We address these issues in a detailed model of the mechanisms underlying facial imitation. The model can be extended to encompass other types of imitation. The model capitalizes on three new theoretical concepts. First, organ identification is the means by which infants relate parts of their own bodies to corresponding ones of the adult's. Second, body babbling (infants' movement practice gained through self-generated activity) provides experience mapping movements to the resulting body configurations. Third, organ relations provide the metric by which infant and adult acts are perceived in commensurate terms. In imitating, infants attempt to match the organ relations they see exhibited by the adults with those they feel themselves make. We show how development restructures the meaning and function of early imitation. We argue that important aspects of later social cognition are rooted in the initial cross-modal equivalence between self and other found in newborns. ©1997 John Wiley & Sons, Ltd.
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paper_title: The role of variability in early development

paper_content:

A rough cutter rotary mining tool formed of a support lug having an elongated, open ended, cylindrical bore and a cutter bit having a cylindrical shank portion extending through and loosely fitted within the bore, with the cutter head portion extending a distance beyond the forward end of the bore. An integral shoulder portion is arranged between the head and shank portions for engaging the lug at the forward end of the bore and a removable retaining clip is mounted upon the free end of the shank portion for engaging the rear end of the lug at the bore. The shank portion is loosely movable endwise a short distance relative to the bore. Also, the diameter of the shank portion is considerably smaller than the bore portion to form a space therebetween and so that the shank may easily rotate within and move transversely of the bore. Thus, small sand-like particles may pass through the bore around the shank during use of the tool.
---
paper_title: Solving Bernstein's Problem: A Proposal for the Development of Coordinated Movement by Selection

paper_content:

In recent years, many established concepts in the theory of human motor development have undergone profound change, and our knowledge has increased greatly. Nevertheless, some outstanding problems remain unsolved. A central problem concerns the redundancy of effective movements, first pointed out by N. A. Bernstein. The human motor system is mechanically complex and can make use of large number of degrees of freedom. The controlled operation of such a system requires a reduction of mechanical redundancy, effectively by reducing the number of degrees of freedom. More recent work has shown that this problem is hard to solve explicitly by computing solutions to the equations of motion of the system. Equally challenging to traditional computational approaches is the fact the motor systems show remarkable adaptability and flexibility in the presence of changing biomechanical properties of motor organs during development and when faced with different environmental conditions or tasks. Solutions to these problems would have a large impact on a variety of issues in child development. In this article, we stress the importance of the somatic selection of neuronal groups in maps for the progressive transformation of a primary movement repertoire into a set of motor synergies and adaptive action patterns. We present results from computer simulations of a simple motor system that works according to such selectional principles. This approach suggests a provisional solution to Bernstein's problem and provides new parameters to guide experimental approaches to the development of sensorimotor coordination.
---
paper_title: Cellular, synaptic and network effects of neuromodulation

paper_content:

All network dynamics emerge from the complex interaction between the intrinsic membrane properties of network neurons and their synaptic connections. Nervous systems contain numerous amines and neuropeptides that function to both modulate the strength of synaptic connections and the intrinsic properties of network neurons. Consequently network dynamics can be tuned and configured in different ways, as a function of the actions of neuromodulators. General principles of the organization of modulatory systems in nervous systems include: (a) many neurons and networks are multiply modulated, (b) there is extensive convergence and divergence in modulator action, and (c) some modulators may be released extrinsically to the modulated circuit, while others may be released by some of the circuit neurons themselves, and act intrinsically. Some of the computational consequences of these features of modulator action are discussed.
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paper_title: Women, fire, and dangerous things : what categories reveal about the mind

paper_content:

"Its publication should be a major event for cognitive linguistics and should pose a major challenge for cognitive science. In addition, it should have repercussions in a variety of disciplines, ranging from anthropology and psychology to epistemology and the philosophy of science. . . . Lakoff asks: What do categories of language and thought reveal about the human mind? Offering both general theory and minute details, Lakoff shows that categories reveal a great deal." David E. Leary, "American Scientist""
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paper_title: A Dynamic Systems Approach to the Development of Cognition and Action

paper_content:

A Dynamic Systems Approach to the Development of Cognition and Action presents a comprehensive and detailed theory of early human development based on the principles of dynamic systems theory. Beginning with their own research in motor, perceptual, and cognitive development, Thelen and Smith raise fundamental questions about prevailing assumptions in the field. They propose a new theory of the development of cognition and action, unifying recent advances in dynamic systems theory with current research in neuroscience and neural development. In particular, they show how by processes of exploration and selection, multimodal experiences form the bases for self-organizing perception-action categories. Thelen and Smith offer a radical alternative to current cognitive theory, both in their emphasis on dynamic representation and in their focus on processes of change. Among the first attempt to apply complexity theory to psychology, they suggest reinterpretations of several classic issues in early cognitive development. The book is divided into three sections. The first discusses the nature of developmental processes in general terms, the second covers dynamic principles in process and mechanism, and the third looks at how a dynamic theory can be applied to enduring puzzles of development. Cognitive Psychology series
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paper_title: Value-dependent selection in the brain: simulation in a synthetic neural model

paper_content:

Abstract Many forms of learning depend on the ability of an organism to sense and react to the adaptive value of its behavior. Such value, if reflected in the activity of specific neural structures (neural value systems), can selectively increase the probability of adaptive behaviors by modulating synaptic changes in the circuits relevant to those behaviors. Neuromodulatory systems in the brain are well suited to carry out this process since they respond to evolutionarily important cues (innate value), broadcast their responses to widely distributed areas of the brain through diffuse projections, and release substances that can modulate changes in synaptic strength. The main aim of this paper is to show that, if value-dependent modulation is extended to the inputs of neural value systems themselves, initially neutral cues can acquire value. This process has important implications for the acquisition of behavioral sequences. We have used a synthetic neural model to illustrate value-dependent acquisition of a simple foveation response to a visual stimulus. We then examine the improvement that ensues when the connections to the value system are themselves plastic and thus become able to mediate acquired value. Using a second-order conditioning paradigm, we demonstrate that auditory discrimination can occur in the model in the absence of direct positive reinforcement and even in the presence of slight negative reinforcement. The discriminative responses are accompanied by value-dependent plasticity of receptive fields, as reflected in the selective augmentation of unit responses to valuable sensory cues. We then consider the time-course during learning of the responses of the value system and the transfer of these responses from one sensory modality to another. Finally, we discuss the relation of value-dependent learning to models of reinforcement learning. The results obtained from these simulations can be directly related to various reported experimental findings and provide additional support for the application of selectional principles to the analysis of brain and behavior.
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paper_title: Neural Darwinism: The Theory of Neuronal Group Selection

paper_content:

Somatic Selection * A Summary and Historical Introduction * Structure, Function, and Perception * Neuronal Group Selection Epigenetic Mechanisms * Developmental Bases of Diversity: The Primary Repertoire * Cellular Dynamics of Neural Maps * Evolution and Function of Distributed Systems * Synapses as Populations: The Bases of the Secondary Repertoire Global Functions * Action and Perception * Categorization and Memory * Selective Networks and Recognition Automata * Selection, Learning, and Behavior Conclusion * Summary, Predictions, and Implications
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paper_title: Consciousness : how matter becomes imagination

paper_content:

Part 1 The world knot: consciousness - philosophical paradox or scientific object? the special problem of consciousness everyman's private theatre - ongoing unity, endless variety. Part 2 Consciousness and the brain: building a picture of the brain consciousness and distributed neural activity neural activity integrated and differentiated. Part 3 Mechanisms of consciousness - the Darwinian perspective: selectionism nonrepresentational memory perception into memory - the remembered present. Part 4 Dealing with plethora - the dynamic core hypothesis: integration and reentry consciousness and complexity determining where the knot is tied - the dynamic core hypothesis. Part 5 Untangling the knot: qualia and discrimination the conscious and the unconscious. Part 6 Observer time: language and the self thinking prisoners of description.
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paper_title: The artificial life roots of artificial intelligence

paper_content:

Behavior-oriented Artificial Intelligence (AI) is a scientific discipline that studies how behavior of agents emerges and becomes intelligent and adaptive. Success of the field is defined in terms of success in building physical agents that are capable of maximizing their own self-preservation in interaction with a dynamically changing environment. The paper addresses this Artificial Life route toward AI and reviews some of the results obtained so far.
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paper_title: Intelligence without Representation

paper_content:

Brooks, R.A., Intelligence without representation, Artificial Intelligence 47 (1991) 139159. Artificial intelligence research has foundered on the issue of representation. When intelligence is approached in an incremental manner, with strict reliance on interfacing to the real world through perception and action, reliance on representation disappears. In this paper we outline our approach to incrementally building complete intelligent Creatures. The fundamental decomposition of the intelligent system is not into independent information processing units which must interface with each other via representations. Instead, the intelligent system is decomposed into independent and parallel activity producers which all interface directly to the world through perception and action, rather than interface to each other particularly much. The notions of central and peripheral systems evaporateeverything is both central and peripheral. Based on these principles we have built a very successful series of mobile robots which operate without supervision as Creatures in standard office environments.
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paper_title: Kicking, rocking, and waving: Contextual analysis of rhythmical stereotypies in normal human infants

paper_content:

Abstract I analysed the triggering contexts of over 14 000 bouts of rhythmical stereotypies of the legs, arms, and whole torso observed in 20 normal infants during their first year. Infant stereotypies were elicited by a wide variety of contexts including non-alert states, interactions with the caregiver and other persons, feeding situations, object interest, and kinaesthetic changes. The frequency of stereotypy in all contexts was a function of age. Non-alert states and interactions with the caregiver were disproportionately associated with leg and torso stereotypies. The relationship between these human stereotypies and the function and control of stereotyped behaviour in other species is discussed.
---
paper_title: Recognition of affective communicative intent in robot-directed speech

paper_content:

Human speech provides a natural and intuitive interface for both communicating with humanoid robots as well as for teaching them. In general, the acoustic pattern of speech contains three kinds of information: who the speaker is, what the speaker said, and how the speaker said it. This paper focuses on the question of recognizing affective communicative intent in robot-directed speech without looking into the linguistic content. We present an approach for recognizing four distinct prosodic patterns that communicate praise, prohibition, attention, and comfort to preverbal infants. These communicative intents are well matched to teaching a robot since praise, prohibition, and directing the robot's attention to relevant aspects of a task, could be used by a human instructor to intuitively facilitate the robot's learning process. We integrate this perceptual ability into our robot's “emotion” system, thereby allowing a human to directly manipulate the robot's affective state. This has a powerful organizing influence on the robot's behavior, and will ultimately be used to socially communicate affective reinforcement. Communicative efficacy has been tested with people very familiar with the robot as well as with naïve subjects.
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paper_title: Four-Month-Old Infants Prefer to Listen to Motherese"

paper_content:

The speech register used by adults with infants and young children, known as motherese, is linguistically simplified and characterized by high pitch and exaggerated intonation. This study investigated infant selective listening to motherese speech. The hypothesis tested was that infants would choose to listen more often to motherese when given the choice between a variety of natural infant-directed and adult-directed speech samples spoken by four women unfamiliar to the subjects. Forty-eight 4-month-old infants were tested in an operant auditory preference procedure. Infants showed a significant listening preference for the motherese speech register.
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paper_title: Social Situatedness of Natural and Artificial Intelligence: Vygotsky and Beyond

paper_content:

The concept of “social situatedness,” that is, the idea that the development of individual intelligence requires a social (and cultural) embedding, has recently received much attention in cognitive science and artificial intelligence research, in particular work on social or epigenetic robotics. The work of Lev Vygotsky, who put forward this view as early as the 1920s, has influenced the discussion to some degree but still remains far from well known. This article therefore is aimed at giving an overview of his cognitive development theory and a discussion of its relation to more recent work in primatology and socially situated artificial intelligence, in particular humanoid robotics.
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paper_title: Behavior-Based Early Language Development on a Humanoid Robot

paper_content:

We are exploring the idea that early language acquisition could be better modelled on an artifcial creature by considering the pragmatic aspect of natural language and of its development in human infants. We have implemented a system of vocal behaviors on Kismet in which "words" or concepts are behaviors in a competitive hierarchy. This paper reports on the framework, the vocal system's architecture and algorithms, and some preliminary results from vocal label learning and concept formation.
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paper_title: Foundations for a Theory of Mind for a Humanoid Robot

paper_content:

Human social dynamics rely upon the ability to correctly attribute beliefs, goals, and percepts to other people. The set of abilities that allow an individual to infer these hidden mental states based on observed actions and behavior has been called a “theory of mind” (Premack & Woodruff, 1978). Existing models of theory of mind have sought to identify a developmental progression of social skills that serve as the basis for more complex cognitive abilities. These skills include detecting eye contact, identifying self-propelled stimuli, and attributing intent to moving objects. ::: If we are to build machines that interact naturally with people, our machines must both interpret the behavior of others according to these social rules and display the social cues that will allow people to naturally interpret the machine's behavior. ::: Drawing from the models of Baron-Cohen (1995) and Leslie (1994), a novel architecture called embodied theory of mind was developed to link high-level cognitive skills to the low-level perceptual abilities of a humanoid robot. The implemented system determines visual saliency based on inherent object attributes, high-level task constraints, and the attentional states of others. Objects of interest are tracked in real-time to produce motion trajectories which are analyzed by a set of naive physical laws designed to discriminate animate from inanimate movement. Animate objects can be the source of attentional states (detected by finding faces and head orientation) as well as intentional states (determined by motion trajectories between objects). Individual components are evaluated by comparisons to human performance on similar tasks, and the complete system is evaluated in the context of a basic social learning mechanism that allows the robot to mimic observed movements. (Copies available exclusively from MIT Libraries, Rm. 14-0551, Cambridge, MA 02139-4307. Ph. 617-253-5668; Fax 617-253-1690.)
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paper_title: Studying robot social cognition within a developmental psychology framework

paper_content:

The paper discusses two prominent theories of cognitive development and relates them to experiments in social robotics. The main difference between these theories lies in the different views on the relationship between a child and its social environment: a) the child as a solitary thinker (Piaget) and b) the child in society (Vygotsky). We discuss the implications this has on the design of socially intelligent agents, focusing on robotic agents. We argue that the framework proposed by Vygotsky provides a promising research direction in autonomous agents. We give examples of implementations in the area of social robotics which support our theoretical considerations. More specifically, we demonstrate how a teacher-learner setup can be used to teach a robot a proto-language. The same control architecture is also used for a humanoid doll robot which can interact with a human by imitation. Another experiment addresses dynamic coupling of movements between a human and a mobile robot. Here, emergent robot-human interaction dynamics are influenced by the temporal coordination between the robot's and the human's movements.
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paper_title: Imitation in Animals and Artifacts

paper_content:

The effort to explain the imitative abilities of humans and other animals draws on fields as diverse as animal behavior, artificial intelligence, computer science, comparative psychology, neuroscience, primatology, and linguistics. This volume represents a first step toward integrating research from those studying imitation in humans and other animals, and those studying imitation through the construction of computer software and robots. Imitation is of particular importance in enabling robotic or software agents to share skills without the intervention of a programmer and in the more general context of interaction and collaboration between software agents and humans. Imitation provides a way for the agent -- whether biological or artificial -- to establish a "social relationship" and learn about the demonstrator's actions, in order to include them in its own behavioral repertoire. Building robots and software agents that can imitate other artificial or human agents in an appropriate way involves complex problems of perception, experience, context, and action, solved in nature in various ways by animals that imitate.
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paper_title: A Dynamic Systems Approach to the Development of Cognition and Action

paper_content:

A Dynamic Systems Approach to the Development of Cognition and Action presents a comprehensive and detailed theory of early human development based on the principles of dynamic systems theory. Beginning with their own research in motor, perceptual, and cognitive development, Thelen and Smith raise fundamental questions about prevailing assumptions in the field. They propose a new theory of the development of cognition and action, unifying recent advances in dynamic systems theory with current research in neuroscience and neural development. In particular, they show how by processes of exploration and selection, multimodal experiences form the bases for self-organizing perception-action categories. Thelen and Smith offer a radical alternative to current cognitive theory, both in their emphasis on dynamic representation and in their focus on processes of change. Among the first attempt to apply complexity theory to psychology, they suggest reinterpretations of several classic issues in early cognitive development. The book is divided into three sections. The first discusses the nature of developmental processes in general terms, the second covers dynamic principles in process and mechanism, and the third looks at how a dynamic theory can be applied to enduring puzzles of development. Cognitive Psychology series
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paper_title: Is imitation learning the route to humanoid robots?

paper_content:

Summary This review investigates two recent developments in artificial intelligence and neural computation: learning from imitation and the development of humanoid robots. It will be postulated that the study of imitation learning offers a promising route to gain new insights into mechanisms of perceptual motor control that could ultimately lead to the creation of autonomous humanoid robots. Imitation learning focuses on three important issues: efficient motor learning, the connection between action and perception, and modular motor control in form of movement primitives. It will be reviewed how research on representations of, and functional connections between action and perception have contributed to our understanding of motor acts of other beings. The recent discovery that some areas in the primate brain are active during both movement perception and execution has provided a hypothetical neural basis of imitation. Computational approaches to imitation learning will also be described, initially from the perspective of traditional AI and robotics, but also from the perspective of neural network models and statistical learning research. Parallels and differences between biological and computational approaches to imitation will be highlighted and an overview of current projects that actually employ imitation learning for humanoid robots will be given.
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paper_title: A survey of socially interactive robots

paper_content:

This paper reviews “socially interactive robots”: robots for which social human–robot interaction is important. We begin by discussing the context for socially interactive robots, emphasizing the relationship to other research fields and the different forms of “social robots”. We then present a taxonomy of design methods and system components used to build socially interactive robots. Finally, we describe the impact of these robots on humans and discuss open issues. An expanded version of this paper, which contains a survey and taxonomy of current applications, is available as a technical report [T. Fong, I. Nourbakhsh, K. Dautenhahn, A survey of socially interactive robots: concepts, design and applications, Technical Report No. CMU-RI-TR-02-29, Robotics Institute, Carnegie Mellon University, 2002]. © 2003 Elsevier Science B.V. All rights reserved.
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paper_title: Explaining facial imitation: a theoretical model

paper_content:

A long-standing puzzle in developmental psychology is how infants imitate gestures they cannot see themselves perform (facial gestures). Two critical issues are: (a) the metric infants use to detect cross-modal equivalences in human acts and (b) the process by which they correct their imitative errors. We address these issues in a detailed model of the mechanisms underlying facial imitation. The model can be extended to encompass other types of imitation. The model capitalizes on three new theoretical concepts. First, organ identification is the means by which infants relate parts of their own bodies to corresponding ones of the adult's. Second, body babbling (infants' movement practice gained through self-generated activity) provides experience mapping movements to the resulting body configurations. Third, organ relations provide the metric by which infant and adult acts are perceived in commensurate terms. In imitating, infants attempt to match the organ relations they see exhibited by the adults with those they feel themselves make. We show how development restructures the meaning and function of early imitation. We argue that important aspects of later social cognition are rooted in the initial cross-modal equivalence between self and other found in newborns. ©1997 John Wiley & Sons, Ltd.
---
paper_title: From visuo-motor self learning to early imitation-a neural architecture for humanoid learning

paper_content:

Behavior imitation ability will be a key technology for future human friendly robots. In order to understand the principles and mechanisms of imitation, we take a synthetic cognitive developmental approach, starting with minimum components and create a system that can learn to imitate others. We developed a visuo-motor neural learning system which consists of orientation selective visual movement representation, distributed arm movement representation, and a high-dimensional temporal sequence learning mechanism. The vision and the movement representations model the findings in primate brain, i.e. macaque area MT(or human area V5) and the primary motor area. The learning mechanism is inspired by the finding that there are excessive connections in neonate brain. As our robot explores the visuo-motor self movement patterns, it learns coherent patterns as high-dimensional trajectory attractors. After the learning, a human comes in front of the robot showing arm movements which are similar to the ones in self learning. Although the robot has never seen or programmed to interpret human arm movement, and the detail of visual stimuli are very different, the robot identifies some of the patterns as similar to those in self learning, and responded by generating the previously learned arm movement. In other words, the robot exhibits early imitation ability based on self exploratory learning.
---
paper_title: Robot fostering techniques for sensory-motor development of humanoid robots

paper_content:

The research efforts addressing the control of robot behavior have been polarized; most robots are either fully guided through “strong” programming, or given a few learning algorithms and left alone to explore the world. This paper explores the area in-between, looking at robot fostering, referring to techniques by which skills can be transferred to robots through a close interaction with humans. While robot fostering can be the basis of interaction with a variety of robotic shapes, it is most natural and human-friendly when the robot apprentices are anthropomorphic/humanoid. Fostering techniques discussed here include teaching/learning by imitation, teaching by description/explanation, reinforcement, aid and collaboration. The paper illustrates an experiment in teaching/learning by imitation. The human fosters the robot by first imitating its uncoordinated arm movements, thus helping the robot develop its sensory-motor associative system. The human then shows arm movements and the robot visually tracks them; consecutively, the robot is able to learn arm movements by imitation. Fostering techniques, in addition to robot learning/acquisition techniques and more efficient man–machine interaction are considered key elements contributing to the nascence of a new research field, developmental robotics, which would focus on the robotics counterpart of human cognitive and motor development. © 2001 Published by Elsevier Science B.V.
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paper_title: Developing Haptic and Visual Perceptual Categories for Reaching and Grasping with a Humanoid Robot

paper_content:

Abstract Properties of the human embodiment — sensorimotor apparatus and neurological structure — participate directly in the growth and development of cognitive processes against enormous worst case complexity. It is our position that relationships between morphology and perception over time lead to increasingly comprehensive models that describe the agent’s relationship to the world. We are applying insight derived from neuroscience, neurology, and developmental psychology to the design of advanced robot architectures. To investigate developmental processes, we have begun to approximate the human sensorimotor configuration and to engage sensory and motor subsystems in developmental sequences. Many such sequences have been documented in studies of infant development, so we intend to bootstrap cognitive structures in robots by emulating some of these growth processes that bear an essential resemblance to the human morphology. In this paper, we will show two related examples in which a humanoid robot determines the models and representations that govern its behavior. The first is a model that captures the dynamics of a haptic exploration of an object with a dextrous robot hand that supports skillful grasping. The second example constructs constellations of visual features to predict relative hand/object postures that lead reliably to haptic utility. The result is a first step in a trajectory toward associative visual-haptic categories that bounds the incremental complexity of each stage of development.
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paper_title: Evolutionary Robotics: The Biology, Intelligence, and Technology of Self-Organizing Machines

paper_content:

Evolutionary robotics is a new technique for the automatic creation of autonomous robots. Inspired by the Darwinian principle of selective reproduction of the fittest, it views robots as autonomous artificial organisms that develop their own skills in close interaction with the environment and without human intervention. Drawing heavily on biology and ethology, it uses the tools of neural networks, genetic algorithms, dynamic systems, and biomorphic engineering. The resulting robots share with simple biological systems the characteristics of robustness, simplicity, small size, flexibility, and modularity. In evolutionary robotics, an initial population of artificial chromosomes, each encoding the control system of a robot, is randomly created and put into the environment. Each robot is then free to act (move, look around, manipulate) according to its genetically specified controller while its performance on various tasks is automatically evaluated. The fittest robots then "reproduce" by swapping parts of their genetic material with small random mutations. The process is repeated until the "birth" of a robot that satisfies the performance criteria. This book describes the basic concepts and methodologies of evolutionary robotics and the results achieved so far. An important feature is the clear presentation of a set of empirical experiments of increasing complexity. Software with a graphic interface, freely available on a Web page, will allow the reader to replicate and vary (in simulation and on real robots) most of the experiments.
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paper_title: Machine Psychology: Autonomous Behavior, Perceptual Categorization and Conditioning in a Brain-based Device

paper_content:

In studying brain activity during the behavior of living animals, it is not possible simultaneously to analyze all levels of control from molecular events to motor responses. To provide insights into how levels of control interact, we have carried out synthetic neural modeling using a brain-based real-world device. We describe here the design and performance of such a device, designated Darwin VII, which is guided by computer-simulated analogues of cortical and subcortical structures. All levels of Darwin VII’s neural architecture can be examined simultaneously as the device behaves in a real environment. Analysis of its neural activity during perceptual categorization and conditioned behavior suggests neural mechanisms for invariant object recognition, experience-dependent perceptual categorization, first-order and second-order conditioning, and the effects of different learning rates on responses to appetitive and aversive events. While individual Darwin VII exemplars developed similar categorical responses that depended on exploration of the environment and sensorimotor adaptation, each showed highly individual patterns of changes in synaptic strengths. By allowing exhaustive analysis and manipulation of neuroanatomy and largescale neural dynamics, such brain-based devices provide valuable heuristics for understanding cortical interactions. These devices also provide the groundwork for the development of intelligent machines that follow neurobiological rather than computational principles in their construction.
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paper_title: Neural plasticity and cognitive development.

paper_content:

It has been well documented that the effects of early occurring brain injury are often attenuated relative to later occurring injury. The traditional neuropsychological account of these observations is that, although the developing neural system normally proceeds along a well-specified maturational course, it has a transient capacity for plastic reorganization that can be recruited in the wake of injury. This characterization of early neural plasticity is limited and fails to capture the much more pervasive role of plasticity in development. This article examines the role of neural plasticity in development and learning. Data from both animal and human studies show that plasticity plays a central role in the normal development of neural systems allowing for adaptation and response to both exogenous and endogenous input. The capacity for reorganization and change is a critical feature of neural development, particularly in the postnatal period. Subtractive processes play a major role in the shaping and sculpting of neural organization. However, plasticity is neither transient nor unique to developing organisms. With development, neural systems stabilize and optimal patterns of functioning are achieved. Stabilization reduces, but does not eliminate, the capacity of the system to adapt. As the system stabilizes, plasticity becomes a less prominent feature of neural functioning, but it is not absent from the adult system. The implications of this broader view of plasticity for our understanding of development following early brain damage are discussed.
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paper_title: Sensory-Motor Coordination: The Metaphor and Beyond

paper_content:

Any agent in the real world has to be able to make distinctions between different types of objects, i.e. it must have the competence of categorization. In mobile agents, there is a large variation in proximal sensory stimulation originating from the same object. Therefore, categorization behavior is hard to achieve, and the successes in the past in solving this problem have been limited. In this paper it is proposed that the problem of categorization in the real world is significantly simplified if it is viewed as one of sensory—motor coordination, rather than one of information processing happening “on the input side”. A series of models are presented to illustrate the approach. It is concluded that we should consider replacing the metaphor of information processing for intelligent systems by the one of sensory-motor coordination. However, the principle of sensory-motor coordination is more than a metaphor. It offers concrete mechanisms for putting agents to work in the real world. These ideas are illustrated with a series of experiments.
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paper_title: Learning of oculo-motor control: a prelude to robotic imitation

paper_content:

In order to allow robot agents to adapt their behaviour, a new approach-learning by imitation-has been proposed, in which a robot learns novel behaviours through interactions with the environment and other agents. In this paper we describe how our sighted agent, ESCHeR -who is equipped with dual foveated lenses and can control head, neck and eye joints-develops fine oculo-motor control through interaction with the environment. ESCHeR successfully learns to coordinate pan, tilt and vergence such that he can track bright moving objects and saccade rapidly to new objects of interest. In developmental terms, ESCHeR can be considered to have progressed from stage 1 to stage 2 of imitation learning. A novel representation of visual scenes is then introduced, and it is discussed how ESCHeR will use this to progress to stage 3.
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paper_title: A Developmental Approach to Visually-Guided Reaching in Artificial Systems

paper_content:

The aim of the present paper is to propose that the adoption of a framework of biological development is suitable for the construction of artificial systems. We will argue that a developmental approach does provide unique insights on how to build highly complex and adaptable artificial systems. To illustrate our point, we will use as an example the acquisition of goal-directed reaching. In the initial part of the paper we will outline (a) how mechanisms of biological development can be adapted to the artificial world, and (b) how this artificial development differs from traditional engineering approaches to robotics. An experiment performed on an artificial system initially controlled by motor reflexes is presented, showing the acquisition of visuo-motor maps for ballistic control of reaching without explicit knowledge of the system's kinematic parameters.
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paper_title: Infant Bouncing: The Assembly and Tuning of Action Systems

paper_content:

We outline a theory of infant skill acquisition characterized by an assembly phase, during which a task-specific, low-dimensional action pattern emerges from spontaneous movement in the context of task constraints, and a tuning phase, during which adjustment of the system parameters yields a more energetically efficient and more stable movement. 8 infants were observed longitudinally when bouncing while supported by a harness attached to a spring. We found an initial assembly phase in which kicking was irregular and variable in period, and a tuning phase with more periodic kicking, followed by the sudden appearance of long bouts of sustained bouncing. This "peak" behavior was characterized by oscillation at the resonant frequency of the mass-spring system, an increase in amplitude, and a decrease in period variability. The data are consistent with a forced mass-spring operating at resonance.
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paper_title: Limitations on input as a basis for neural organization and perceptual development: A preliminary theoretical statement

paper_content:

We propose an alternative to the conventional view that limitations on infant functioning are handicaps to be overcome. According to our view, limitations, particularly of the sensory systems, produce adaptive advantages for infants by facilitating perceptual organization. During embryogenesis, developmental rates of sensory systems are unequal so that onset of functioning is sequential. We argue that such differential onset results in relative independence among emerging systems, thereby reducing competition which helps regulate subsequent neurogenesis and functioning. In addition to prenatal effects, neonatal sensory limitations are discussed as a major source of perceptual organization. Limitations reduce the amount of information with which the infant must contend and promote temporal contiguity between multimodal attributes of a stimulus. Although we focus on human perceptual development, our view is a broadly based comparative one. Thus, other organisms have evolved means of restricting sensory input, and evidence is cited suggesting the importance of this reduced input in regulating normal perceptual development.
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paper_title: Robots as cognitive tools: Information theoretic analysis of sensory-motor data

paper_content:

In this paper we explore the possibility of quantitative analysis of sensory data and the interactions between the signals in different sensory channels as an agent interacts with the real world, in order to get a better intuition of these data which constitute, in a sense, the “raw material” that the neural system has to process. This will give us also a handle on formulating some of the design principles of autonomous agents, which we had worked out in earlier research, in a more quantitative way. As an example of an analysis, we employ information theoretic measures, such as the Shannon Entropy and the Mutual Information. We hope that the insights emerging from this research will eventually lead to a more formal description of some of the design principles of autonomous agents.
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paper_title: The adaptive nature of cognitive immaturity.

paper_content:

The prolonged cognitive immaturity characteristic of human youth is described as adaptive in and of itself. The adaptive nature of cognitive immaturity is examined in developmental research in the areas of metacognition, egocentricity, plasticity and the speed of information processing, and language acquisition. Some of the consequences of viewing children's immature cognition as adaptive for cognitive development and education are discussed.
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paper_title: Perceived self in infancy

paper_content:

Research is presented suggesting that an implicit sense of self is developing from birth, long before children begin to manifest explicit (conceptual) self-knowledge by the second year. Implicit self-knowledge in infancy is rooted in intermodal perception and action. Studies are reported showing that at least from 2 months of age, infants become increasingly systematic and deliberate in the exploration of their own body and the perceptual consequences of self-produced action. From such exploration, infants develop a sense of their own body as a differentiated entity, situated and agent in the environment. Based on recent empirical findings, the perceptual determinants of such implicit sense of self are discussed.
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paper_title: A model of the neuro-musculo-skeletal system for human locomotion

paper_content:

The generation of human locomotion was examined by linking computational neuroscience with biomechanics from the perspective of nonlinear dynamical theory. We constructed a model of human locomotion, which includes a musculo-skeletal system with 8 segments and 20 muscles, a neural rhythm generator composed of 7 pairs of neural oscillators, and mechanisms for processing and transporting sensory and motor signals. Using a computer simulation, we found that locomotion emerged as a stable limit cycle that was generated by the global entrainment between the musculo-skeletal system, the neural system, and the environment. Moreover, the walking movements of the model could be compared quantitatively with those of experimental studies in humans.
---
paper_title: Explaining facial imitation: a theoretical model

paper_content:

A long-standing puzzle in developmental psychology is how infants imitate gestures they cannot see themselves perform (facial gestures). Two critical issues are: (a) the metric infants use to detect cross-modal equivalences in human acts and (b) the process by which they correct their imitative errors. We address these issues in a detailed model of the mechanisms underlying facial imitation. The model can be extended to encompass other types of imitation. The model capitalizes on three new theoretical concepts. First, organ identification is the means by which infants relate parts of their own bodies to corresponding ones of the adult's. Second, body babbling (infants' movement practice gained through self-generated activity) provides experience mapping movements to the resulting body configurations. Third, organ relations provide the metric by which infant and adult acts are perceived in commensurate terms. In imitating, infants attempt to match the organ relations they see exhibited by the adults with those they feel themselves make. We show how development restructures the meaning and function of early imitation. We argue that important aspects of later social cognition are rooted in the initial cross-modal equivalence between self and other found in newborns. ©1997 John Wiley & Sons, Ltd.
---
paper_title: From visuo-motor self learning to early imitation-a neural architecture for humanoid learning

paper_content:

Behavior imitation ability will be a key technology for future human friendly robots. In order to understand the principles and mechanisms of imitation, we take a synthetic cognitive developmental approach, starting with minimum components and create a system that can learn to imitate others. We developed a visuo-motor neural learning system which consists of orientation selective visual movement representation, distributed arm movement representation, and a high-dimensional temporal sequence learning mechanism. The vision and the movement representations model the findings in primate brain, i.e. macaque area MT(or human area V5) and the primary motor area. The learning mechanism is inspired by the finding that there are excessive connections in neonate brain. As our robot explores the visuo-motor self movement patterns, it learns coherent patterns as high-dimensional trajectory attractors. After the learning, a human comes in front of the robot showing arm movements which are similar to the ones in self learning. Although the robot has never seen or programmed to interpret human arm movement, and the detail of visual stimuli are very different, the robot identifies some of the patterns as similar to those in self learning, and responded by generating the previously learned arm movement. In other words, the robot exhibits early imitation ability based on self exploratory learning.
---
paper_title: Plasticity in Value Systems and its Role in Adaptive Behavior

paper_content:

Adaptive behavior requires the sensing of salient behavioral consequences which can act to modulate changes in neural connections linking sensory and motor structures. In previous work, we proposed that salient sensory events trigger neuronal value systems capable of modulating synaptic plasticity. Here, we investigate the capacity of value systems to modulate their own responses in the context of various conditioning tasks. To this end, we implement a modifiable value system incorporating anatomical and physiological properties within Darwin V, a neuronal model embedded in a mobile real world device. While exploring an environment containing stimulus objects, Darwin V's visual maps develop object-related neuronal responses. Phasic responses of a value system initially triggered only by object-"taste" (innate value) modulate changes in connections between visual and motor neurons, thus linking specific visual responses to appropriate motor outputs. Over time, Darwin V is able behaviorally to discriminate ...
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paper_title: Specification of Neocortical Areas and Thalamocortical Connections

paper_content:

The mammalian neocortex has six main layers distinguished by neuronal morphology and density. Like the other distinct regions of the adult cerebral cortex, the neocortex is divided into functionally specialized areas that are anatomically distinguishable based on differences in connectional and archi­ tectural features (Brodmann 1909). These differences, as well as the modality of afferent input, dictate an area's functional identity. However, many features of the vertical organization of the neocortex, such as cell number per radial traverse (Rockel et al 1980, Hendry et al 1987), intrinsic circuitry (Gilbert 1983, Metin & Frost 1989, Sur et al 1988), and laminar organization of classes of input and output projections, (Jones 1984, McConnell 1988, 1989, O'Leary 1989) are consistent between areas of the adult neocortex, and even betweeri mammalian species. An emerging view is that these common features of vertical organization are specified in the neuroepithelium (McConnell 1989, 1991, Katz & Callaway 1992). Even more prominent than the many similarities between neocortical areas are certain "area-specific" features, which include differences in connectivity and architecture with sharp borders delimiting these areas. Here we consider the relative contributions of genetic and epigenetic mechanisms in the emergence of area-specific features during neocortical development. In addition, because many studies indicate that
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paper_title: Behavioral constraints in the development of neuronal properties: a cortical model embedded in a real-world device.

paper_content:

The ability of organisms to categorize diverse and often novel stimuli depends on ongoing interactions with their environment. In a modality such as vision, categorization requires the generation of both selective and invariant responses of cortical neurons to complex visual stimuli. How does behavior contribute to shaping the responses of these neurons? Analysis of this question is made difficult by the complex multilevel interactions between many neural and behavioral variables. To mitigate this difficulty, we studied the development and ongoing plasticity of pattern-selective neuronal responses by means of synthetic neural modeling. For this purpose, we constructed Darwin V, which consists of a simulated neuronal model embedded in a real-world device that is capable of motion and autonomous behavior. The neuronal model consists of four major components: a visual system (containing cortical and subcortical networks); a taste system based on conductance; sets of motor neurons capable of triggering behavior; and a diffuse ascending (value) system. The modeled visual cortex consists of two areas: a topographic map responsive to elementary features connected to a higher-order map composed of initially non-selective neuronal units. During behavior over time in its environment, Darwin V encounters numerous objects consisting of black metal cubes displaying different patterns of white blobs and stripes. Initially, the lack of specific higher-order visual responses does not allow visual pattern discrimination, and appetitive and aversive behaviors are triggered by the ‘taste’ (surface conductivity of objects) alone. In the course of sensory experience, however, changes occur in visual and sensorimotor connection strengths, with two major consequences. First, units within the higher visual area acquire responses that are both pattern selective and translation invariant. Second, as a result of the operation of the value system, these responses become linked to appropriate behaviors. Analysis of Darwin V after such changes indicates that the continuity of self-generated movements is essential for the development of pattern-selective and translationinvariant responses. The concomitant development of a preference for foveal over parafoveal objects was found to be due to increased behavioral interactions with object cubes gripped by the centrally mounted effector (snout) of Darwin V. Finally, even after development of higher-order visual responses, visual responses to more frequently encountered objects continued to be enhanced, while other responses were diminished. Overall, the detailed study of Darwin V over multiple levels of organization provides a heuristically revealing example of the crucial role played by behavioral and environmental interactions in the development of complex responses by specialized neurons.
---
paper_title: Machine Psychology: Autonomous Behavior, Perceptual Categorization and Conditioning in a Brain-based Device

paper_content:

In studying brain activity during the behavior of living animals, it is not possible simultaneously to analyze all levels of control from molecular events to motor responses. To provide insights into how levels of control interact, we have carried out synthetic neural modeling using a brain-based real-world device. We describe here the design and performance of such a device, designated Darwin VII, which is guided by computer-simulated analogues of cortical and subcortical structures. All levels of Darwin VII’s neural architecture can be examined simultaneously as the device behaves in a real environment. Analysis of its neural activity during perceptual categorization and conditioned behavior suggests neural mechanisms for invariant object recognition, experience-dependent perceptual categorization, first-order and second-order conditioning, and the effects of different learning rates on responses to appetitive and aversive events. While individual Darwin VII exemplars developed similar categorical responses that depended on exploration of the environment and sensorimotor adaptation, each showed highly individual patterns of changes in synaptic strengths. By allowing exhaustive analysis and manipulation of neuroanatomy and largescale neural dynamics, such brain-based devices provide valuable heuristics for understanding cortical interactions. These devices also provide the groundwork for the development of intelligent machines that follow neurobiological rather than computational principles in their construction.
---
paper_title: Sensory-Motor Coordination: The Metaphor and Beyond

paper_content:

Any agent in the real world has to be able to make distinctions between different types of objects, i.e. it must have the competence of categorization. In mobile agents, there is a large variation in proximal sensory stimulation originating from the same object. Therefore, categorization behavior is hard to achieve, and the successes in the past in solving this problem have been limited. In this paper it is proposed that the problem of categorization in the real world is significantly simplified if it is viewed as one of sensory—motor coordination, rather than one of information processing happening “on the input side”. A series of models are presented to illustrate the approach. It is concluded that we should consider replacing the metaphor of information processing for intelligent systems by the one of sensory-motor coordination. However, the principle of sensory-motor coordination is more than a metaphor. It offers concrete mechanisms for putting agents to work in the real world. These ideas are illustrated with a series of experiments.
---
paper_title: Growth and repair: Instantiating a biologically-inspired model of neuronal development on the Khepera robot

paper_content:

Activity-dependent, developmental synaptic plasticity permits, in part, an animal's nervous system to be constructed in a way that depends on both the animal's experiences and its body's particular morphology. The continuing expression of this plasticity into later life allows constant adaptation of the animal's nervous system to changes in the animal's body as it grows and ages, also allowing some recovery from major injury. We instantiate a previously-studied model of such neuronal development on a robotic platform to establish whether "developmental robotics" can equip a robot with a nervous system tuned to the robot's individual morphology and that allows recovery from damage.
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paper_title: Development of auditory-evoked reflexes: Visuo-acoustic cues integration in a binocular head

paper_content:

Abstract The goal of this paper is to propose a biologically plausible, functional model of the acquisition of visual, acoustic and multi-modal motor responses. Within this context visual and acoustic spatial cues are considered, fused in a coherent percept and eventually employed to control the orienting behavior of a humanoid robot. The rationale of the approach lies in the possibility to test and empirically prove the correctness of the model through the embodiment and the real interaction of the system with the environment. The model takes into account the fact that (i) acoustic and visual cues are represented with respect to different coordinate frames (head-centric versus retino-centric) and consequently they need to be “aligned” in order to be properly fused, (ii) a teaching signal has to be generated in order to inform the system that the motor performance is not adequate to perform the task (i.e. orient toward the stimulus) and thus adaptation is required, and (iii) vision plays a major role in driving the acquisition of the appropriate map of space but other sources of feedback might be employed as well.
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paper_title: Developmental robotics: manifesto and application

paper_content:

We argue that all embodied organisms, whether robots or animals, face the same challenge: of adapting to bodies, brains and environments that undergo constant and inevitable change. After highlighting the evidence for the universal role of a class of molecular factors called neurotrophic factors in the response of animals to this challenge, we suggest that implementing models of neurotrophic interactions on robots may confer on them the adaptability and robustness exhibited by animals. We briefly review a mathematical model of neurotrophic interactions and then discuss its application in a robotic context. Finally, we examine the potential, or otherwise, of our approach to developmental robotics.
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paper_title: Self-organized control of bipedal locomotion by neural oscillators in unpredictable environment

paper_content:

A new principle of sensorimotor control of legged locomotion in an unpredictable environment is proposed on the basis of neurophysiological knowledge and a theory of nonlinear dynamics. Stable and flexible locomotion is realized as a global limit cycle generated by a global entrainment between the rhythmic activities of a nervous system composed of coupled neural oscillators and the rhythmic movements of a musculo-skeletal system including interaction with its environment. Coordinated movements are generated not by slaving to an explicit representation of the precise trajectories of the movement of each part but by dynamic interactions among the nervous system, the musculo-skeletal system and the environment. The performance of a bipedal model based on the above principle was investigated by computer simulation. Walking movements stable to mechanical perturbations and to environmental changes were obtained. Moreover, the model generated not only the walking movement but also the running movement by changing a single parameter nonspecific to the movement. The transitions between the gait patterns occurred with hysteresis.
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paper_title: Foundations for a Theory of Mind for a Humanoid Robot

paper_content:

Human social dynamics rely upon the ability to correctly attribute beliefs, goals, and percepts to other people. The set of abilities that allow an individual to infer these hidden mental states based on observed actions and behavior has been called a “theory of mind” (Premack & Woodruff, 1978). Existing models of theory of mind have sought to identify a developmental progression of social skills that serve as the basis for more complex cognitive abilities. These skills include detecting eye contact, identifying self-propelled stimuli, and attributing intent to moving objects. ::: If we are to build machines that interact naturally with people, our machines must both interpret the behavior of others according to these social rules and display the social cues that will allow people to naturally interpret the machine's behavior. ::: Drawing from the models of Baron-Cohen (1995) and Leslie (1994), a novel architecture called embodied theory of mind was developed to link high-level cognitive skills to the low-level perceptual abilities of a humanoid robot. The implemented system determines visual saliency based on inherent object attributes, high-level task constraints, and the attentional states of others. Objects of interest are tracked in real-time to produce motion trajectories which are analyzed by a set of naive physical laws designed to discriminate animate from inanimate movement. Animate objects can be the source of attentional states (detected by finding faces and head orientation) as well as intentional states (determined by motion trajectories between objects). Individual components are evaluated by comparisons to human performance on similar tasks, and the complete system is evaluated in the context of a basic social learning mechanism that allows the robot to mimic observed movements. (Copies available exclusively from MIT Libraries, Rm. 14-0551, Cambridge, MA 02139-4307. Ph. 617-253-5668; Fax 617-253-1690.)
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paper_title: Building brains for bodies

paper_content:

We describe a project to capitalize on newly available levels of computational resources in order to understand human cognition. We are building an integrated physical system including vision, sound input and output, and dextrous manipulation, all controlled by a continuously operating large scale parallel MIMD computer. The resulting system will learn to “think” by building on its bodily experiences to accomplish progressively more abstract tasks. Past experience suggests that in attempting to build such an integrated system we will have to fundamentally change the way artificial intelligence, cognitive science, linguistics, and philosophy think about the organization of intelligence. We expect to be able to better reconcile the theories that will be developed with current work in neuroscience.
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paper_title: Intelligence without Representation

paper_content:

Brooks, R.A., Intelligence without representation, Artificial Intelligence 47 (1991) 139159. Artificial intelligence research has foundered on the issue of representation. When intelligence is approached in an incremental manner, with strict reliance on interfacing to the real world through perception and action, reliance on representation disappears. In this paper we outline our approach to incrementally building complete intelligent Creatures. The fundamental decomposition of the intelligent system is not into independent information processing units which must interface with each other via representations. Instead, the intelligent system is decomposed into independent and parallel activity producers which all interface directly to the world through perception and action, rather than interface to each other particularly much. The notions of central and peripheral systems evaporateeverything is both central and peripheral. Based on these principles we have built a very successful series of mobile robots which operate without supervision as Creatures in standard office environments.
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paper_title: Is imitation learning the route to humanoid robots?

paper_content:

Summary This review investigates two recent developments in artificial intelligence and neural computation: learning from imitation and the development of humanoid robots. It will be postulated that the study of imitation learning offers a promising route to gain new insights into mechanisms of perceptual motor control that could ultimately lead to the creation of autonomous humanoid robots. Imitation learning focuses on three important issues: efficient motor learning, the connection between action and perception, and modular motor control in form of movement primitives. It will be reviewed how research on representations of, and functional connections between action and perception have contributed to our understanding of motor acts of other beings. The recent discovery that some areas in the primate brain are active during both movement perception and execution has provided a hypothetical neural basis of imitation. Computational approaches to imitation learning will also be described, initially from the perspective of traditional AI and robotics, but also from the perspective of neural network models and statistical learning research. Parallels and differences between biological and computational approaches to imitation will be highlighted and an overview of current projects that actually employ imitation learning for humanoid robots will be given.
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paper_title: From earwigs to humans

paper_content:

Both direct, and evolved, behavior-based approaches to mobile robots have yielded a number of interesting demonstrations of robots that navigate, map, plan and operate in the real world. The work can best be described as attempts to emulate insect-level locomotion and navigation, with very little work on behavior-based non-trivial manipulation of the world. There have been some behavior-based attempts at exploring social interactions, but these too have been modeled after the sorts of social interactions we see in insects. But thinking how to scale from all this insect-level work to full human-level intelligence and social interactions leads to a synthesis that is very different from that imagined in traditional Artificial Intelligence and Cognitive Science. We report on work towards that goal.
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paper_title: A survey of socially interactive robots

paper_content:

This paper reviews “socially interactive robots”: robots for which social human–robot interaction is important. We begin by discussing the context for socially interactive robots, emphasizing the relationship to other research fields and the different forms of “social robots”. We then present a taxonomy of design methods and system components used to build socially interactive robots. Finally, we describe the impact of these robots on humans and discuss open issues. An expanded version of this paper, which contains a survey and taxonomy of current applications, is available as a technical report [T. Fong, I. Nourbakhsh, K. Dautenhahn, A survey of socially interactive robots: concepts, design and applications, Technical Report No. CMU-RI-TR-02-29, Robotics Institute, Carnegie Mellon University, 2002]. © 2003 Elsevier Science B.V. All rights reserved.
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paper_title: Can development be designed? What we may learn from the Cog project

paper_content:

Neither design nor evolutionary approaches to building behaviorbased robots feature a role for development in the genesis of behavioral organization. However, the new Cog Project aims to build a humanoid robot that will display behavioral abilities observed in human infants; and proposes making use of ideas from evolution and developmental psychology in its design. This paper provisionally evaluates this work from a developmental perspective, to show how developmental study may offer not only a source of phenomena for modelling but also a method that contributes to our understanding of self-organization. Cog's design methodology confronts problems with selection and interpretation of component behaviors, and how these may be better understood through appropriate developmental study is illustrated. Cog's design principles are shown to exhibit interesting convergences with infant mechanisms, based on the significance of emergent functionality and the action- as opposed to representation-based nature of initial and outcome mechanisms, but analysis of infants suggests a more constructive view of ability is required.
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paper_title: Cognitive developmental robotics as a new paradigm for the design of humanoid robots

paper_content:

This paper proposes cognitive developmental robotics(CDR) as a new principle for the design of humanoid robots. This principle may provide ways of understanding human beings that go beyond the current level of explanation found in the natural and social sciences. Furthermore, a methodological emphasis on humanoid robots in the design of artificial creatures holds promise because they have many degrees of freedom and sense modalities and, thus, must face the challenges of scalability that are often side-stepped in simpler domains. We examine the potential of this new principle as well as issues that are likely to be important to CDR in the future. © 2001 Elsevier Science B.V. All rights reserved.
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paper_title: From visuo-motor self learning to early imitation-a neural architecture for humanoid learning

paper_content:

Behavior imitation ability will be a key technology for future human friendly robots. In order to understand the principles and mechanisms of imitation, we take a synthetic cognitive developmental approach, starting with minimum components and create a system that can learn to imitate others. We developed a visuo-motor neural learning system which consists of orientation selective visual movement representation, distributed arm movement representation, and a high-dimensional temporal sequence learning mechanism. The vision and the movement representations model the findings in primate brain, i.e. macaque area MT(or human area V5) and the primary motor area. The learning mechanism is inspired by the finding that there are excessive connections in neonate brain. As our robot explores the visuo-motor self movement patterns, it learns coherent patterns as high-dimensional trajectory attractors. After the learning, a human comes in front of the robot showing arm movements which are similar to the ones in self learning. Although the robot has never seen or programmed to interpret human arm movement, and the detail of visual stimuli are very different, the robot identifies some of the patterns as similar to those in self learning, and responded by generating the previously learned arm movement. In other words, the robot exhibits early imitation ability based on self exploratory learning.
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paper_title: Alternative essences of intelligence

paper_content:

We present a novel methodology for building humanlike artificially intelligent systems. We take as a model the only existing systems which are universally accepted as intelligent: humans. We emphasize building intelligent systems which are not masters of a single domain, but, like humans, are adept at performing a variety of complex tasks in the real world. Using evidence from cognitive science and neuroscience, we suggest four alternative essences of intelligence to those held by classical AI. These are the parallel themes of development, social interaction, embodiment, and integration. Following a methodology based on these themes, we have built a physical humanoid robot. In this paper we present our methodology and the insights it affords for facilitating learning, simplifying the computation underlying rich behavior, and building systems that can scale to more complex tasks in more challenging environments.
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paper_title: Learning visual stabilization reflexes in robots with moving eyes

paper_content:

This work addresses the problem of learning stabilization re exes in robots with moving eyes. Most essential in achieving e3cient visual stabilization is the exploitation =integration of di4erent motion related sensory information. In our robot, self-motion is measured inertially with an arti7cial vestibular system and visually using optic ow algorithms. The 7rst sensory system provides short latency measurements of rotations and translations of the robot’s head, the second, a delayed estimate of the motion across the image plane. A self-tuning neural network learns to combine these two measurements and generates oculo-motor compensatory behaviors that stabilize the visual scene. We describe the network architecture and the learning scheme. The stabilization performance is evaluated quantitatively using direct measurements on the image plane. c 2002 Elsevier Science B.V. All rights reserved.
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paper_title: Life Itself: A Comprehensive Inquiry Into the Nature, Origin, and Fabrication of Life

paper_content:

1. Prolegomenon2. Strategic Considerations: The Special and the General3. Some Necessary Epistemological Considerations4. The Concept of State5. Entailment Without States: Relational Biology6. Analytic and Synthetic Models7. On Simulation8. Machines and Mechanisms9. Relational Theory of Machines10. Life Itself: The Preliminary Steps11. Relational Biology and Biology
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paper_title: Self-repairing mechanical systems

paper_content:

A concept of a self-repairable mechanical system which is composed of homogeneous mechanical units is described. We have developed a modular system capable of 'self-assembly' and self-repair. The former means a set of units can form a given shape of the system without outside help, and the latter means the system restores the original shape if an arbitrary part of the system cut off. We show both of 2D and 3D unit design, and distributed algorithm for the units.© (1999) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
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paper_title: Emergent Forms: Origins and Early Development of Human Action and Perception

paper_content:

Part I: Ecological and Dynamical Foundations 1. Fundamental Issues and Perspectives in the Development of Action 2. From Bernstein and von Holst to Dynamical Systems Complexity 3. Ecological Foundations 4. The Components of Action Systems: Subsystems and Their Interaction Part II: Self-Organization and Selection as the Basis for the Assembly of Action Systems 5. Spontaneous Pattern Formation 6. Selection and the Emergence of Specialized Functions 7. The Ontogeny of Action Systems: A Theory Part III: The Action Systems 8. Basic Orienting 9. Appetition 10. Locomotion 11. The Performatory Action System: Manual Activity 12. The Expressive Action System 13. Directions
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paper_title: Evolutionary Robotics: The Biology, Intelligence, and Technology of Self-Organizing Machines

paper_content:

Evolutionary robotics is a new technique for the automatic creation of autonomous robots. Inspired by the Darwinian principle of selective reproduction of the fittest, it views robots as autonomous artificial organisms that develop their own skills in close interaction with the environment and without human intervention. Drawing heavily on biology and ethology, it uses the tools of neural networks, genetic algorithms, dynamic systems, and biomorphic engineering. The resulting robots share with simple biological systems the characteristics of robustness, simplicity, small size, flexibility, and modularity. In evolutionary robotics, an initial population of artificial chromosomes, each encoding the control system of a robot, is randomly created and put into the environment. Each robot is then free to act (move, look around, manipulate) according to its genetically specified controller while its performance on various tasks is automatically evaluated. The fittest robots then "reproduce" by swapping parts of their genetic material with small random mutations. The process is repeated until the "birth" of a robot that satisfies the performance criteria. This book describes the basic concepts and methodologies of evolutionary robotics and the results achieved so far. An important feature is the clear presentation of a set of empirical experiments of increasing complexity. Software with a graphic interface, freely available on a Web page, will allow the reader to replicate and vary (in simulation and on real robots) most of the experiments.
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paper_title: A unifying computational framework for motor control and social interaction

paper_content:

Recent empirical studies have implicated the use of the motor system during action observation, imitation and social interaction. In this paper, we explore the computational parallels between the processes that occur in motor control and in action observation, imitation, social interaction and theory of mind. In particular, we examine the extent to which motor commands acting on the body can be equated with communicative signals acting on other people and suggest that computational solutions for motor control may have been extended to the domain of social interaction.
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paper_title: A Dynamic Systems Approach to the Development of Cognition and Action

paper_content:

A Dynamic Systems Approach to the Development of Cognition and Action presents a comprehensive and detailed theory of early human development based on the principles of dynamic systems theory. Beginning with their own research in motor, perceptual, and cognitive development, Thelen and Smith raise fundamental questions about prevailing assumptions in the field. They propose a new theory of the development of cognition and action, unifying recent advances in dynamic systems theory with current research in neuroscience and neural development. In particular, they show how by processes of exploration and selection, multimodal experiences form the bases for self-organizing perception-action categories. Thelen and Smith offer a radical alternative to current cognitive theory, both in their emphasis on dynamic representation and in their focus on processes of change. Among the first attempt to apply complexity theory to psychology, they suggest reinterpretations of several classic issues in early cognitive development. The book is divided into three sections. The first discusses the nature of developmental processes in general terms, the second covers dynamic principles in process and mechanism, and the third looks at how a dynamic theory can be applied to enduring puzzles of development. Cognitive Psychology series
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paper_title: Sensors and actuators for 'humanoid' robots

paper_content:

Though much research is still necessary before a personal robot with anthropomorphic features becomes a full reality, accessible and appealing to the general user, present technology is able to offer many solutions to the different problems arising in the development of sensors and actuators, which are a key factor in the achievement of the final goal. However, the challenge of obtaining a humanoid robot combining adequate technical performance with a 'behavior' appealing for a real 'companion' to the human user requires a truly interdisciplinary effort involving not only technical disciplines, but also the contribution of human sciences. This paper presents the motivations for the development of sensors and actuators for humanoid robots, with particular emphasis on service robotics and on the concept of a personal robot. A brief survey of existing technologies is reported and a few examples of present implementations are described. We also present the main features of a real personal robot whose technica...
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paper_title: The Knowledge Tree: The Biological Roots of Human Understanding

paper_content:

A trimmer mechanism has an improved drive assembly for intermittently moving sheets of material relative to trim knives. The drive assembly includes a single cam member having a pair of cam surfaces which operate two linkages to rotate a crankarm. Each linkage includes a follower link on which a cam follower is mounted in engagement with an associated one of the cam surfaces and a drive link which is connected with the crankarm. Upon rotation of the cam member, the follower links are moved in such a manner as to move the two drive links to apply transversely directed forces to the crankarm. These transversely directed forces cause the crankarm to move along a circular path. The cam surfaces have a configuration such that the two linkages are ineffective to drive the crankarm once the sheets of material have been moved into position relative to the trim knives. During the time in which the crankarm is stationary, the trim knives are moved to trim the sheets of material.
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paper_title: "CAM-Brain" ATR's billion neuron artificial brain project: a three year progress report

paper_content:

This paper reports on progress made in the first 3 years of ATR's CAM-Brain Project, which aims to use evolutionary engineering techniques to build/grow/evolve a RAM-and-cellular-automata based artificial brain consisting of thousands of interconnected neural network modules inside special hardware such as MIT's Cellular Automata Machine CAM-8, or NTT's Content Addressable Memory System CAM-System. The states of a billion (later a trillion) 3D cellular automata cells, and millions of cellular automata rules which govern their state changes, can be stored relatively cheaply in giga(tera)bytes of RAM. After 3 years work, the CA rules are almost ready. MIT's CAM-8 (essentially a serial device) can update 200 million CA cells a second. It is likely that NTT's CAM-System (essentially a massively parallel device) will be able to update a hundred billion CA cells a second. Hence all the ingredients will soon be ready to create a revolutionary new technology which will allow thousands of evolved neural network modules to be assembled into artificial brains. This in turn will probably create not only a new research field, but hopefully a whole new industry, namely brain building. Building artificial brains with a billion neurons is the aim of ATR's 8 year CAM-Brain research project, ending in 2001.
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paper_title: Autopoiesis: a review and a reappraisal

paper_content:

The aim of the paper is to review critically the notion of autopoiesis as presented by Maturana and Varela. In particular, recognizing that there are difficulties in obtaining a complete and clear picture from the primary literature, an effort is made to present a coherent view-also based on many years of personal contact with Francisco Varela. The paper begins with a few historical notes to highlight the cultural background from which the notion of autopoiesis arose. The basic principles of autopoiesis as a theory of cellular life are then described, emphasizing also what autopoiesis is not: not an abstract theory, not a concept of artificial life, not a theory about the origin of life-but rather a pragmatic blueprint of life based on cellular life. It shown how this view leads to a conceptually clear definition of minimal life and to a logical link with related notions, such as self-organization, emergence, biological autonomy, auto-referentiality, and interactions with the environment. The perturbations brought about by the environment are seen as changes selected and triggered by the inner organization of the living. These selective coupling interactions impart meaning to the minimal life and are thus defined by Maturana and Varela with the arguable term of "cognition". This particular view on the mutual interactions between living organism and environment leads these authors to the notion of "enaction", and to the surprising view that autopoiesis and cognition are two complementary, and in a way equivalent, aspects of life. It is then shown how cognition, so defined, permits us to build a bridge between biology and cognitive science. Autopoiesis also allows one to conceive chemical models of minimal cellular life that can be implemented experimentally. The corresponding work on "chemical autopoiesis" is then reviewed. The surprising impact of autopoiesis in the social sciences ("social autopoiesis") is also briefly discussed. This review also comments on why the theory of autopoiesis had, and still has, a difficult time being accepted into the mainstream of life-science research. Finally, it is pointed out that the new interest in system biology and complexity theories may lead to a reappraisal of autopoiesis and related notions, as outlined also by other authors, such as Tibor Ganti and Stuart Kauffmann.
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paper_title: From earwigs to humans

paper_content:

Both direct, and evolved, behavior-based approaches to mobile robots have yielded a number of interesting demonstrations of robots that navigate, map, plan and operate in the real world. The work can best be described as attempts to emulate insect-level locomotion and navigation, with very little work on behavior-based non-trivial manipulation of the world. There have been some behavior-based attempts at exploring social interactions, but these too have been modeled after the sorts of social interactions we see in insects. But thinking how to scale from all this insect-level work to full human-level intelligence and social interactions leads to a synthesis that is very different from that imagined in traditional Artificial Intelligence and Cognitive Science. We report on work towards that goal.
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paper_title: Language within our grasp

paper_content:

Abstract In monkeys, the rostral part of ventral premotor cortex (area F5) contains neurons that discharge, both when the monkey grasps or manipulates objects and when it observes the experimenter making similar actions. These neurons (mirror neurons) appear to represent a system that matches observed events to similar, internally generated actions, and in this way forms a link between the observer and the actor. Transcranial magnetic stimulation and positron emission tomography (PET) experiments suggest that a mirror system for gesture recognition also exists in humans and includes Broca's area. We propose here that such an observation/execution matching system provides a necessary bridge from `doing' to `communicating', as the link between actor and observer becomes a link between the sender and the receiver of each message.
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paper_title: Special issue on self-reconfigurable robots

paper_content:

A machine attachment for separating tubular knitted articles knitted in succession and connected each to the next succeeding one by a frangible joining thread, in accordance with which the fabric is gripped above and below a separation line and between the positions of gripping the fabric is deflected laterally by a pusher device until the joining thread is fractured and the leading article separated from the next succeeding one, the separated article being subsequently drawn away through a discharge tube . The pusher device is conveniently formed as part of a short tube through which the fabric from the knitting machine passes, which tube is slidable laterally between upper and lower openings for passage of the fabric, which openings have flaps to close them and provide for the gripping of the fabric.
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Title: Developmental robotics: a survey

Section 1: Introduction
Description 1: Introduce the field of developmental robotics, its interdisciplinary nature, and the motivations behind this research area.

Section 2: In the beginning there was the body
Description 2: Discuss the concept of embodiment and its impact on cognitive processes, contrasting it with traditional cognitive science paradigms.

Section 3: Facets of development
Description 3: Review important aspects and components of ontogenetic development, providing examples and relevant literature pointers.

Section 4: Degrees of freedom and motor activity
Description 4: Explain the developmental progression of motor coordination and control, focusing on the degrees of freedom problem.

Section 5: Self-exploratory activity
Description 5: Highlight the significance of self-exploration in infancy and its role in learning to control the body.

Section 6: Spontaneous activity
Description 6: Describe the function and importance of spontaneous movements in early motor control development.

Section 7: Anticipatory movements and early abilities
Description 7: Explore how infants develop the ability to predict sensory consequences and control anticipatory movements.

Section 8: Categorization and sensorimotor co-ordination
Description 8: Discuss the process of categorization and its reliance on sensorimotor interactions with the environment.

Section 9: Neuromodulation, value and neural plasticity
Description 9: Explain the role of neuromodulatory systems, value systems, and neural plasticity in developmental processes.

Section 10: Research landscape
Description 10: Survey various current and past research projects in developmental robotics, categorizing them into different areas of interest.

Section 11: Socially-oriented interaction
Description 11: Review studies on social interaction and the acquisition of social behaviors in robotic systems.

Section 12: Non-social interaction
Description 12: Examine research on sensorimotor coordination and categorization in non-social contexts.

Section 13: Agent-related control
Description 13: Investigate studies focused on self-exploration and morphological changes in robots.

Section 14: Mechanisms and processes
Description 14: Discuss various mechanistic and process-oriented aspects relevant to developmental robotics.

Section 15: Intermediate discussion
Description 15: Provide observations and insights gained from the reviewed research, highlighting key themes and outstanding issues.

Section 16: Developmental robotics: existing theoretical frameworks
Description 16: Discuss existing theoretical frameworks in developmental robotics, their historical contexts, and contributions to the field.

Section 17: Discussion
Description 17: Summarize the challenges and prospects of designing multi-task intelligent systems, emphasizing the significance of developmental approaches.

Section 18: Future prospects and conclusion
Description 18: Outline future research directions, emphasizing autonomous learning and the integration of value systems, physical growth, morphology, and materials in robotics.