Friday, April 30, 2010

Evaluating effects of genes and environment on early reading.

Work from Taylor et al. studying mono- and dizygotic twins in kindergarten through 5th grade suggests, not suprisingly, that that better teachers allow children to fulfill their genetic potential:

Thursday, April 29, 2010

When do human groups form states?

Spencer suggests that human states evolve (without contact with any preexisting states) when the area controlled by a group becomes larger than a day's round trip from the capital:
A major research problem in anthropology is the origin of the state and its bureaucratic form of governance. Of particular importance for evaluating theories of state origins are cases of primary state formation, whereby a first-generation state evolves without contact with any preexisting states. A general model of this process, the territorial-expansion model, is presented and assessed with archaeological data from six areas where primary states emerged in antiquity: Mesoamerica, Peru, Egypt, Mesopotamia, the Indus Valley, and China. In each case, the evidence shows a close correspondence in time between the first appearance of state institutions and the earliest expansion of the state's political-economic control to regions lying more than a day's round-trip from the capital. Although additional research will add detail and clarity to the empirical record, the results to date are consistent with the territorial-expansion model, which argues that the success of such long-distance expansion not only demanded the bureaucratization of central authority but also helped provide the resources necessary to underwrite this administrative transformation.

Wednesday, April 28, 2010

Do brain training programs work?




Tuesday, April 27, 2010

Old age improves reasoning about social conflicts

Interesting observation from Grossmann et al.:
It is well documented that aging is associated with cognitive declines in many domains. Yet it is a common lay belief that some aspects of thinking improve into old age. Specifically, older people are believed to show better competencies for reasoning about social dilemmas and conflicts. Moreover, the idea of aging-related gains in wisdom is consistent with views of the aging mind in developmental psychology. However, to date research has provided little evidence corroborating this assumption. We addressed this question in two studies, using a representative community sample. We asked participants to read stories about intergroup conflicts and interpersonal conflicts and predict how these conflicts would unfold. We show that relative to young and middle-aged people, older people make more use of higher-order reasoning schemes that emphasize the need for multiple perspectives, allow for compromise, and recognize the limits of knowledge. Our coding scheme was validated by a group of professional counselors and wisdom researchers. Social reasoning improves with age despite a decline in fluid intelligence. The results suggest that it might be advisable to assign older individuals to key social roles involving legal decisions, counseling, and intergroup negotiations. Furthermore, given the abundance of research on negative effects of aging, this study may help to encourage clinicians to emphasize the inherent strengths associated with aging.

Monday, April 26, 2010

Internet enhancing, not diminishing, the public square.




How pain impairs cognition

Ji et al. use an animal model of arthritis pain to show that pain-related cognitive deficits result from amygdala-driven impairment of medial prefrontal cortical (mPFC) function.

Friday, April 23, 2010

Oxytocin enhances social learning as well as empathy.

From Hurlemann et al.:
Oxytocin (OT) is becoming increasingly established as a prosocial neuropeptide in humans with therapeutic potential in treatment of social, cognitive, and mood disorders. However, the potential of OT as a general facilitator of human learning and empathy is unclear. The current double-blind experiments on healthy adult male volunteers investigated first whether treatment with intranasal OT enhanced learning performance on a feedback-guided item–category association task where either social (smiling and angry faces) or nonsocial (green and red lights) reinforcers were used, and second whether it increased either cognitive or emotional empathy measured by the Multifaceted Empathy Test. Further experiments investigated whether OT-sensitive behavioral components required a normal functional amygdala. Results in control groups showed that learning performance was improved when social rather than nonsocial reinforcement was used. Intranasal OT potentiated this social reinforcement advantage and greatly increased emotional, but not cognitive, empathy in response to both positive and negative valence stimuli. Interestingly, after OT treatment, emotional empathy responses in men were raised to levels similar to those found in untreated women. Two patients with selective bilateral damage to the amygdala (monozygotic twins with congenital Urbach–Wiethe disease) were impaired on both OT-sensitive aspects of these learning and empathy tasks, but performed normally on nonsocially reinforced learning and cognitive empathy. Overall these findings provide the first demonstration that OT can facilitate amygdala-dependent, socially reinforced learning and emotional empathy in men.

Thursday, April 22, 2010

The brain's default mode, our ego, and Freud


The best illusion of the year contest

The top ten candidates for the 2010 best Illusion of the Year context have been chosen. The site show the illusions from previous years' competitions.

Wednesday, April 21, 2010

Doing two things at once splits the brain.

...and we are not very good at managing more than two things at once. Here is the fascinating abstract from Charron and Koechlin:
The anterior prefrontal cortex (APC) confers on humans the ability to simultaneously pursue several goals. How does the brain’s motivational system, including the medial frontal cortex (MFC), drive the pursuit of concurrent goals? Using brain imaging, we observed that the left and right MFC, which jointly drive single-task performance according to expected rewards, divide under dual-task conditions: While the left MFC encodes the rewards driving one task, the right MFC concurrently encodes those driving the other task. The same dichotomy was observed in the lateral frontal cortex, whereas the APC combined the rewards driving both tasks. The two frontal lobes thus divide for representing simultaneously two concurrent goals coordinated by the APC. The human frontal function seems limited to driving the pursuit of two concurrent goals simultaneously.
A figure from the ScienceNow review. When tackling tasks A and B simultaneously, half of the brain handles A (red) while the other handles B (yellow).

Opera singers' brains - and the brain's organization of music knowledge

Numerous studies have shown brain changes that correlate with athletic and musical instrument training. Kleber et al. now extend such work to vocal performance training:
Several studies have shown that motor-skill training over extended time periods results in reorganization of neural networks and changes in brain morphology. Yet, little is known about training-induced adaptive changes in the vocal system, which is largely subserved by intrinsic reflex mechanisms. We investigated highly accomplished opera singers, conservatory level vocal students, and laymen during overt singing of an Italian aria in a neuroimaging experiment. We provide the first evidence that the training of vocal skills is accompanied by increased functional activation of bilateral primary somatosensory cortex representing articulators and larynx. Opera singers showed additional activation in right primary sensorimotor cortex. Further training-related activation comprised the inferior parietal lobe and bilateral dorsolateral prefrontal cortex. At the subcortical level, expert singers showed increased activation in the basal ganglia, the thalamus, and the cerebellum. A regression analysis of functional activation with accumulated singing practice confirmed that vocal skills training correlates with increased activity of a cortical network for enhanced kinesthetic motor control and sensorimotor guidance together with increased involvement of implicit motor memory areas at the subcortical and cerebellar level. Our findings may have ramifications for both voice rehabilitation and deliberate practice of other implicit motor skills that require interoception.
In another article on the brain and music, Omar et al. (open access) compare normal subjects with alzheimer's and dementia patients to find evidence that music knowledge is fractionated, with superordinate musical knowledge relatively more robust than knowledge of particular music. They propose that music constitutes a distinct domain of non-verbal knowledge but shares certain cognitive organizational features with other brain knowledge systems. Within the domain of music knowledge, dissociable cognitive mechanisms process knowledge derived from physical sources and the knowledge of abstract musical entities.

Tuesday, April 20, 2010



Enhanced facial threat detection in elite warriors

Ross et al show that Navy SEALS, compared with a male control group, show more focused neural and performance tuning: greater neural processing resources are directed toward threat stimuli (angry faces), while processing resources are conserved when facing a nonthreatening stimul (fearful or happy faces).

Monday, April 19, 2010

MindBlog's spring home

This picture (click to enlarge) of early spring at my 1860 stone schoolhouse residence in Middleton Wisconsin shows why I recently returned from  winter exile in Fort Lauderdale (which doesn't have seasons). 

Two routes to slowing aging...

Nutrient-sensing pathways are central to the aging process

Single-celled yeast provides a simple model system for studying aging

C. elegans worms are a simple multicellular model system for aging


Studies of rodents may yield leads for human clinical trials

Limited data exist on life-span extension in primates




Friday, April 16, 2010

More detail on money and happiness

Yet another study, this one by Boyce et al. (open access), confirming that money doesn't buy happiness, people gain "utility" from occupying a higher ranked position within an income distribution rather than from either absolute income or their position relative to a reference wage:
Does money buy happiness, or does happiness come indirectly from the higher rank in society that money brings? We tested a rank-income hypothesis, according to which people gain utility from the ranked position of their income within a comparison group. The rank hypothesis contrasts with traditional reference-income hypotheses, which suggest that utility from income depends on comparison to a social reference-group norm. We found that the ranked position of an individual’s income predicts general life satisfaction, whereas absolute income and reference income have no effect. Furthermore, individuals weight upward comparisons more heavily than downward comparisons. According to the rank hypothesis, income and utility are not directly linked: Increasing an individual’s income will increase his or her utility only if ranked position also increases and will necessarily reduce the utility of others who will lose rank.

Thursday, April 15, 2010

Like humans - Leaders, Followers and Schmoozers among animals

Natalie Angier does an interesting article describing work showing that the array of personality types noted within human groups, mostly likely largely due to genetic variation, is seen also in many animal populations (stylistic diversity is seen in chimpanzees, monkeys, barnacle geese, farm minks, blue tits and great tits, bighorn sheep, dumpling squid, pumpkinseed sunfish, zebra finches, spotted hyenas, even spiders and water striders, to name a few). A particular robust parallel is noted with variation in the traits of neophobia (fear of novelty) versus the willingness to explore one’s surroundings (The trait distinctive to birds leading a flock is apparently boldness). Field experiments with birds have now answered the critique that observing these distinct traits in different individuals might be due to the captive environment of laboratory behavioral studies. Researchers have identified:
...hotheads and tiptoers, schmoozers and loners, divas, dullards and fearless explorers.. animals, like us, often cling to the same personality for the bulk of their lives...highly sensitive, arty-type humans have a lot in common with squealing pigs and twitchy mice, and that to call a hypersensitive person thin-skinned or touchy might hold a grain of physical truth.

Wednesday, April 14, 2010

Self control without a self...


Tuesday, April 13, 2010

Lessening moral judgements by a magenetic zap to the brain.

MRI measurements have shown that the the right temporoparietal junction (RTPJ) - an area just above the right ear - receives more blood than usual when we think or read about the beliefs and intentions of other people, particularly if we use the information to judge people negatively. Young et al. show that this area is actually involved in making negative moral judgements, because when it is inactivated by trans cranial magnetic stimulation (TMS), subjects judge an attempted versus an accidental homicide less severely. The abstract:

Monday, April 12, 2010

We separate identity and emotion of a stimulus in under 100 msec.

Liu and Ioannides record the small rapid magnetic signals caused by brain activity (using magnetoencephalography, or MEG) to study whether face affect recognition depends on where the face stimulus (happy, fearful, neutral) appears in the visual field. Emotional appraisal (amygdalar activity) occurs more rapidly than final cognitive appraisal in the pre-frontal cortex - (We jump away from a moving S-shaped figure in our peripheral vision before we have determined whether it is actually a snake). Here is their abstract:
It is now apparent that the visual system reacts to stimuli very fast, with many brain areas activated within 100 ms. It is, however, unclear how much detail is extracted about stimulus properties in the early stages of visual processing. Here, using magnetoencephalography we show that the visual system separates different facial expressions of emotion well within 100 ms after image onset, and that this separation is processed differently depending on where in the visual field the stimulus is presented. Seven right-handed males participated in a face affect recognition experiment in which they viewed happy, fearful and neutral faces. Blocks of images were shown either at the center or in one of the four quadrants of the visual field. For centrally presented faces, the emotions were separated fast, first in the right superior temporal sulcus (STS; 35–48 ms), followed by the right amygdala (57–64 ms) and medial pre-frontal cortex (83–96 ms). For faces presented in the periphery, the emotions were separated first in the ipsilateral amygdala and contralateral STS. We conclude that amygdala and STS likely play a different role in early visual processing, recruiting distinct neural networks for action: the amygdala alerts sub-cortical centers for appropriate autonomic system response for fight or flight decisions, while the STS facilitates more cognitive appraisal of situations and links appropriate cortical sites together. It is then likely that different problems may arise when either network fails to initiate or function properly.

Friday, April 09, 2010

Brain correlates of anticipation and body dysmorphic disorder

For readers who like this sort of stuff, this post is a grab-bag pointing to three recent studies correlating brain activity with behavior, two on anticipation and one on body dysmorphic disorder:

A group at University College London finds that the temporal probability of expected visual events is encoded not by a single area but by a wide network that importantly includes neuronal populations at the very earliest cortical stages of visual processing. Activity in those areas changes dynamically in a manner that closely accords with temporal expectations. (These early stages have generally been thought to be locked to the visual stimulus in an invariant and automatic way. Now they appear to link with higher parietal and motor-related areas known to be involved in anticipation.)

Kahnt et al. show that reward value of sensory cues can be decoded from distributed fMRI patterns in the orbitofrontal cortex, and that value representations in the orbitofronal cortex are independent of whether reward is anticipated or actually received.

Finally, a study from UCLA in the Archives of General Psychiatry finds that subjects with body dysmorphic disorder (i.e., preoccupied with perceived defects in their appearance) show (compared with control subjects) hyperactivity in the left orbitofrontal cortex and bilateral head of the caudate when viewing their own face versus a familiar face. This suggests abnormalities in visual processing and frontostriatal systems in body dysmorphic disorder. The two most effective theraputic approaches to the disorder are cognitive behavioral therapy and treatment with serotonin-enhancing drugs, either alone or in combination. As Brody notes, what does not work is plastic surgery and other cosmetic treatments. Even if the treatments modify one presumed defect, the person is likely to come up with another, and another, and another, leading to a vicious cycle of costly and often deforming as well as ineffective remedies.

Thursday, April 08, 2010

fMRI measurents distinguish specific memories


Wednesday, April 07, 2010

April stirs the dull roots...and MindBlog is on the road.

Today I start my annual migration from Fort Lauderdale (the Winter home) back to Middleton, Wisconsin (the Spring, Summer, and Fall home) - driving with my two Abyssinian cats. A few posts are in the queue to appear, but after that MindBlog postings may be lean or absent for a few days...

Early spring pictures of our Wisconsin home sent by my partner Len show why I return (Florida doesn't have seasons). 

Unconscious control of 'conscious' prefrontal cognitive control.




Tuesday, April 06, 2010

The love that dare not squawk its name.

Various forms of same-sex sexual activity, some of them long term couplings, have been recorded in more than 450 different species of animals by now, "from flamingos to bison to beetles to guppies to warthogs." Jon Mooallem does an interesting article on the topic, whose title is used as the title of this post, in this past Sunday's NY Times Magazine. A few clips, which don't do justice to the breadth of the article:

Different ideas are emerging about how these behaviors could fit within that traditional Darwinian framework, including seeing them as conferring reproductive advantages in roundabout ways...a single explanation of homosexual behavior in animals may not be possible, because thinking of “homosexual behavior in animals” as a single scientific subject might not make much sense...the point of heterosexual matter what kind of animal is doing it, is primarily reproduction. But that shouldn’t trick us into thinking that homosexual behavior has some equivalent, organizing purpose.



Monday, April 05, 2010

A new wave in literary studies - theories of mind

Patricia Cohen writes an article on a new trend in the musty hallways of university English departments,  trying to unite cognitive psychology and literary criticism.  Here are some slightly edited clips:
Why do we read fiction? Why do we care so passionately about nonexistent characters? What underlying mental processes are activated when we read? ...The layered process of figuring out what someone else is thinking — of mind reading — is both a common literary device and an essential survival skill. This capacity is termed 'theory of mind' by cognitive psychologists.

Humans can comfortably keep track of three different mental states at a time. For example, the proposition “Peter said that Paul believed that Mary liked chocolate” is not too hard to follow. Add a fourth level, though, and it’s suddenly more difficult. And experiments have shown that at the fifth level understanding drops off by 60 percent. Modernist authors like Virginia Woolf are especially challenging because she asks readers to keep up with six different mental states, or levels of intentionality...Perhaps the human facility with three levels is related to the intrigues of sexual mating. Do I think he is attracted to her or me?
Experiments are actually planned to perform MRI experiments on subjects exposed to a set of texts of graduated complexity, noting brain areas previously associated with theory of mind operations. Cohen's article notes nother perspective:
...fictional accounts help explain how altruism evolved despite our selfish genes. Fictional heroes are [frequently] “altruistic punishers,” people who right wrongs even if they personally have nothing to gain. “To give us an incentive to monitor and ensure cooperation, nature endows us with a pleasing sense of outrage” at cheaters, and delight when they are punished. We enjoy fiction because it is teeming with altruistic punishers: Odysseus, Don Quixote, Hamlet, Hercule Poirot...It’s not just that evolution gives us insight into fiction, but also that fiction gives us insight into evolution.

Friday, April 02, 2010

A Mozart presto

Final movement of the Mozart from Monday and Wednesday.

Blocking the emotions of old memories.

Dolan and collaborators do an interesting study showing that beta-adrenergic blockers (which are known to block the initial storage of emotions along with declarative memory of an event) can later also strip away the emotional memories associated with an event during its recall, an effect which persists for at least 24 hours in the absence of the blocker . The abstract:
Memory enhancement for emotional events is dependent on amygdala activation and noradrenergic modulation during learning. A potential role for noradrenaline (NE) during retrieval of emotional memory is less well understood. Here, we report that administration of the β-adrenergic receptor antagonist propranolol at retrieval abolishes a declarative memory enhancement for emotional items. Critically, this effect persists at a subsequent 24 h memory test, in the absence of propranolol. Thus, these findings extend our current understanding of the role of NE in emotional memory to encompass effects at retrieval, and provide face validity to clinical interventions using β-adrenergic antagonists in conjunction with reactivation of unwanted memories in anxiety-related disorders.

Thursday, April 01, 2010

Mate preferences predicted by national health.

DeBruine et al have done an interesting study in which 4500 women from 30 different countries in Europe and the Americas went to a Web site ( and noted their preferences between pairs of 20 different white male faces, some of them digitally manipulated to increase or decrease masculine features. They wanted to test the evolutionary psychology suggestion that women may prefer tough-looking guys because their offspring are more likely to survive. (The downside is that manly men tend not to be the best dads, investing fewer resources in their offspring.) The less healthy a woman's country was, the more likely she was to prefer the masculinized faces. Those at the high end of the macho-preferring scale came from Brazil, also ranked as having the worst health. Those who tended more toward the girly men were from Belgium and Sweden, the healthiest. Here is their abstract:

Facilitating choice with a electrical zap to the head

Hecht et al. show that a 2 milliamp direct current from a battery (small and safe, but noticeable to subjects) passed between one saline-soaked surface sponge electrode placed on the head over the left dorsolateral prefrontal cortex (anodal, positive) and another over the right dorsolateral prefrontal cortex (cathodal, negative) causes participants to become quicker in selecting the most frequent alternative in a probabilistic guessing task, suggesting a cognitive facilitation in reasoning and decision-making processes.  Here is their abstract:
In a random sequence of binary events where one alternative occurs more often than the other, humans tend to guess which of the two alternatives will occur next by trying to match the frequencies of previous occurrences. Based on split-brain and unilaterally damaged patients' performances, it has been proposed that the left hemisphere (LH) tends to match the frequencies, while the right hemisphere (RH) tends toward maximizing and always choosing the most frequent alternative. The current study used transcranial direct current stimulation (tDCS) to test this hemispheric asymmetry hypothesis by stimulating the dorsolateral prefrontal cortex of each hemisphere and simultaneously inhibiting the corresponding region in the homotopic hemisphere, while participants were engaged in a probabilistic guessing task. Results showed no difference in strategy between the three groups (RH anodal/LH cathodal, LH anodal/RH cathodal, no stimulation) as participants predominantly matched the frequencies of the two alternatives. However, when anodal tDCS was applied to the LH and cathodal tDCS applied to the RH, participants became quicker to select the most frequent alternative. This finding is in line with previous evidence on the involvement of the LH in probabilistic learning and reasoning and adds to a number of demonstrations of anodal tDCS leading to some behavioral enhancement or change in bias.