Cat intelligence

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Adolescent, semi-feral female tabby anxious to feed

Cat intelligence is the capacity of the domesticated cat to learn, solve problems, and adapt to its environment. Research[which?] has also shown feline intelligence to include the ability to acquire new behavior that applies previously learned knowledge to new situations, communicating needs and desires within a social group, and responding to training cues.[citation needed]


Brain size[edit]

The brain of the domesticated cat is about 5 centimetres (2.0 inches) long and weighs 25–30 g (0.88–1.06 oz).[1][2] If a typical cat is taken to be 60 cm (24 in) long with a weight of 3.3 kg (7.3 lb), then the brain would be at 0.90% (0.91%[3]) of its total body mass, compared to 2.00% (2.33%[3]) of total body mass in the average human. Within the encephalization quotient proposed by Jerison in 1973,[3][4] values above 1 are classified big brained, lower than 1 are small brained.[5] The domestic cat is attributed a value of between 1 – 1.71 relative to human value that is 7.44 – 7.8.[1][3] The largest brain in the cat kingdom are those of the tigers in Java and Bali, of which the largest relative brain size within the pantera is the tigris.[6] It is debated whether there exists a causal relationship between brain size and intelligence in vertebrates. Correlations have been shown between these factors in a number[quantify] of experiments.[which?] However, correlation does not imply causation. Most experiments involving the relevance of brain size to intelligence hinge on the assumption that complex behavior requires a complex (and therefore intelligent) brain; however, this connection has not been consistently demonstrated.[7][8][9][10][11]

The surface area of a cat's cerebral cortex is approximately 83 cm² whereas the human brain has a surface area of about 2500 cm².[12] Furthermore, a theoretical cat weighing 3,500 grams has a cerebellum weighing 5.3 grams, 0.17% of the total weight.[13]

Brain structures[edit]

According to researchers at Tufts University School of Veterinary Medicine, the physical structure of the brains of humans and cats are very similar.[14] The human brain and the cat brain both have cerebral cortices[15] with similar lobes.[16]

The number of cortical neurons contained in the brain of the cat is reported to be 763 million.[17] Area 17[18] of the visual cortex was found to contain about 51,400 neurons per mm3.[19][20] Both human and feline brains are gyrencephalic, i.e. they have a surface folding.[21][22]

Analyses of cat brains have shown they are divided into many areas with specialized tasks that are extremely interconnected and share sensory information in a kind of hub-and-spoke network, with a large number of specialized hubs and many alternate paths between them. This exchange of sensory information allows the brain to construct a complex perception of the real world and to react to and manipulate its environment.[23]

The thalamus of the cat[24][25] constituting a hypothalamus,[26] epithalamus, ventral and dorsal parts[27] and including a lateral geniculate nucleus,[28] and additional secondary nuclear structures are responsible for controlling impulses to the cortex, functions of sleep, memory originally formed of sensory datum, and cellular functioning otherwise unknown, as yet not fully understood (unnaccounted for[29][30]). The thalamus has neuronal connectivity to the cerebellum.[31]

Grouse et al. 1979 ascertained the neuroplasticity of kittens' brains, with respect to control of visual stimulus correlated with changes in RNA structures.[32] In a later study, it was found that cats possess visual-recognition memory,[33][34] and have flexibility of cerebral encoding from visual information, adaptability corresponding to changing environmental stimuli.[35]

Secondary brain structures[edit]

The domestic cat brain also contains the hippocampus,[36] amygdala,[37] frontal lobes (which comprise 3 to 3.5% of the total brain in cats compared to about 25% in humans),[38][39] corpus callosum,[40][41] anterior commisure,[42] pineal gland,[43] caudate nucleus, septal nuclei and midbrain.[44]

Brain and diet[edit]

Main article: Cat food

For the optimum health and functioning[45][46][47] of the brain, a cat would require primarily manganese, potassium, Vitamin D, Vitamin B1, and Vitamin B6. Calcium, sodium, magnesium, and Vitamin A should be provided as part of a nutritionally balanced diet. Additionally, taurine is an essential amino acid in a cat's diet: taurine insufficiency leads to retinal degeneration and blindness in cats.[citation needed]


American tabby

Intelligence through behavioural observation is defined as a composite of skills and abilities.[48] The WAIS test is a measure of intelligence in adult homo sapiens. The test scores on four criteria; verbal comprehension, perceptual organisation, working memory and processing speed.[49] In a comparative evaluation from WAIS criteria, cats are generally fair in intelligence.[citation needed] The working memory for object permanence of the domesticated cat is surmised from experiment as being 16 hours.[50]

Factors that contribute to greater intelligence are the velocity at which electrical transmission is conducted and with the greater number of cortical neurons.[51] Compared to mammalian species this number was eleven-fourteenth in total.[1][52]

Experimental results seemed to indicate that cats have no capacity for object permanence, as defined through investigation by J. Piaget with infants.[53] Further research made to identify a similar factor of cognition showed behaviour indicative of object permanence cognition, although of a different type to that identified initially by Piaget.[54][55] Further research showed that the animal has an awareness of objects not directly available to sight, and also sensory-motor intelligence comparable with a two-year old child.[56] In experimental conditions, the memory of a cat was demonstrated as having an information-retention or recall, of a duration totaling as much as 10 years.[57]

Some studies have suggested that cats may dream.[58][59][60]


Taken as a whole, cats have excellent memories.[citation needed] However, relationships with humans, individual differences in intelligence, and age may affect memory. Cats adapt to the environment that they are in easily because they can recall what they have learned in the past and adapt these memories to the current situation to protect themselves throughout their lives.[61][62]


For kittens, play is more than simple enjoyment and fun in the animal world. These things rank social order and prey-capturing skills and hone the cat for survival. In addition to this, they are exercising their minds and bodies in rehearsal for their adult roles. Before they were domesticated, kittens learned survival skills such as where to find food from observing their mothers. The first two to seven weeks are a critical time for kittens. This is when they bond with other cats. Without any human contact during this time, the cat would forever mistrust humans, according to some experts.[who?][61]

Older cats[edit]

Just as in humans, advancing age may affect memory in cats. Some cats may experience a weakening of both learning ability and memory that affects them adversely in ways similar to those occurring in poorly aging humans. A slowing of function is normal, and this includes memory. Aging may affect memory by changing the way their brain stores information and by making it harder to recall stored information. Cats lose brain cells as they age, just as humans do.[63] The older the cat, the more these changes can affect its memory. There have been no studies done on the memories of aging cats and memory, but there is some speculation[by whom?] that, just like people, short term memory is more affected by aging. However, research says that adult cats have a short-term memory span of 16 hours compared to only 5 hours in adult dogs especially when it benefits the cat directly.[citation needed]

Diseases may affect memory[edit]

Disease may also affect cat memory. There is a syndrome called Feline Cognitive Dysfunction (FCD) that is similar to Alzheimer's disease in humans. The symptoms include disorientation, reduced social interaction, sleep disturbances, and loss of house training. This syndrome causes degenerative changes in the brain that are the source of the functional impairment.[63]

Domestication effect[edit]

See also: Felidae and Wildcat

Cat intelligence study is mostly from consideration of the domesticated cat. The process of domestication has allowed for closer observation of cat behaviour and in the increased incidence of interspecies communication,[64][65] the inherent plasticity of the cat's brain has become apparent as the number of studies in this have increased scientific insight. Changes in the genetic structure of a number of cats has been identified[66][67] as a consequence of both domestication practises and the activity of breeding, so that the species has undergone genetic evolutionary change due to human selection.[66][67] The domesticated cat developed by artificial selection to possess characteristics desirable for the sharing of human habitation and living, coupled with an initial naturally occurring selective set of cat-choices made while interacting with Neolithic urban environments.[68]

The intelligence of the cat is believed to be largely dependent upon its inter-species relations,[citation needed] e.g. between H. sapiens and F. catus, and is reflected in responses in the stress hormones released in cats kept from exploratative behaviours. That is to say, an enriched and stimulating environment produced by exploring urban places increased the likelihood of cerebral plasticity due to the need of situations requiring novel adaptive behaviours.[69] This scavenging behaviour[70][71] would only have produced slow changes in evolutionary terms. Such changes are comparable to the changes to the brain[72] of early primitive hominids who co-existed with primitive cats, like Machairodontinae, Megantereon and Homotherium, and adapted to savannah conditions.[73][74][75][76]


Xenarthra (late cretaceous)
(armadillos, anteaters, sloths)

Pholidota (late cretaceous)

Epitheria (latest Cretaceous)

(some extinct groups) X

moles, tenrecs)


Zalambdalestidae X (late Cretaceous)

Macroscelidea (late Eocene)
(elephant shrews)

Anagaloidea X

Glires (early Paleocene)

Lagomorpha (Eocene)(rabbits, hares, pikas)

Rodentia (late Paleocene)
(mice & rats, squirrels, porcupines)


Scandentia (mid Eocene)
(tree shrews)


Plesiadapiformes X

Primates (early Paleocene)
(tarsiers, lemurs, monkeys, apes including humans)

Dermoptera (late Eocene)

Chiroptera (late Paleocene)

Carnivora (early Paleocene)
(cats, dogs, bears, seals)

Ungulatomorpha (late Cretaceous)
Eparctocyona (late Cretaceous)

(some extinct groups) X

Arctostylopida X (late Paleocene)

Mesonychia X (mid Paleocene)
(predators / scavengers, but not closely related to modern carnivores)


Cetacea (early Eocene)
(whales, dolphins, porpoises)

Artiodactyla (early Eocene)
(even-toed ungulates: pigs, hippos, camels, giraffes, cattle, deer)


Hilalia X

Perissodactyla (late Paleocene)
(odd-toed ungulates: horses, rhinos, tapirs)

Tubulidentata (early Miocene)

Paenungulata ("not quite ungulates")

Hyracoidea (early Eocene)

Sirenia (early Eocene)
(manatees, dugongs)

Proboscidea(early Eocene)

Considering the fossil-based family tree of placental mammals[77] above; the feline line diverged many years previously from the primate line; the cat both feral and domesticated is likely to be maintained in a stasis by its niche position in the current food web.[78]

Learning capacity[edit]

Javan tiger photographed by Andries Hoogerwerf in Ujung Kulon National Park, 1938[79]

The cats in the key experiments conducted by Edward Thorndike were able to learn through operant conditioning.[80] In Thorndike's experiment, cats were placed in various boxes approximately 20 inches long, 15 inches wide, and 12 inches tall with a door opened by pulling a weight attached to it. The cats were observed to free themselves from the boxes by "trial and error with accidental success."[80][81] In one test the cat was shown to have done worse in a later trial than in an earlier one, suggesting that no learning from the previous trials was retained in long-term memory.[82] The scientist considered the cat to have the capacity for learning due to the law of effect, which states that responses followed by satisfaction (i.e. a reward) become more likely responses to the same stimulus in the future.[81]

An experiment was conducted in 2009 where cats could pull on a string to retrieve a treat under a plastic screen. When presented with one string, cats had no trouble getting the treats. When presented with multiple strings, some of which were not connected to treats, the cats were unable to consistently choose the correct strings, leading to the conclusion that cats do not understand cause and effect in the same way that humans do.[83][84] Thorndike was skeptical of the presence of intelligence in cats, criticising sources of the contemporary writing of the sentience of animals as "partiality in deductions from facts and more especially in the choice of facts for investigation."[85]

Research was made to identify possible observational learning in kittens. Kittens that were able to observe their mothers performing an experimentally organised act were able to perform the same act sooner than kittens that had observed a non-related adult cat, and sooner than the ones who, being placed in trial and error conditions, observed no other cat performing the act.[86][87][88] Experimental investigation of primates show that the chimpanzee possess some limited insight in regard to observational learning (see Köhler), whereas this capacity is wholly absent in the domesticated cat,[clarification needed][89][90] P. leo, and P. tigris.

The effect of training[edit]

Main article: Animal training

Cats are known to be trained as circus animals,[91] although traditionally considered difficult mainly because they appear to assume such behaviors only in exchange for a direct benefit.[citation needed] A good example of this is The Yuri Kuklachev Cat Theatre based in Moscow,[92] the owner of which has been training cats for many years to do a full range of circus-style tricks. Also there is the belief that cats are difficult to train owing to impatience and boredom with the training exercise.[citation needed]

Artificial intelligence[edit]

In assessing the limitations resulting from the genetic propensity that the cat as a species has for adaption to a more intelligent biological state through evolutionary means,[93] animal integrity is cited a reason that genetic transformation of animals should not proceed.[94][95][96]

In considering the unlikely likelihood of the cat developing intelligence should the opportunity for longitudinal evolutionary changes occur, e.g. if humanity becomes extinct, the likelihood of an evolution of pantera intelligence within the millions-of-years time-scale identified by the evolution of human intelligence studies is a factor of genetics.[citation needed]

Since 2006, when the entire DNA constituents in sequence of the Abyssinian cat were made into a genetic map of the Felis catus,[97][98] genetically engineering some form of enhanced cat intelligence has become theoretically possible, although it is presently unlikely to ever be created due to ethical restrictions as well as practical considerations. Artificially enhanced cat intelligence would therefore only become a consideration for use in experiment, perhaps at some unknown time in future. The production of more intelligent cats might be theoretically a consideration for military organisations i.e. DARPA, in the hope of gleaning some advancement in warfare. Practically the common cat has proved little use for military personnel (Acoustic Kitty), despite the potential inherent in a creature with far greater prowess and agility than any human.[citation needed]

In November 2009, scientists simulated a cat's brain using a supercomputer[99] containing 24,576 processors.[100][101] This experiment did not simulate the function of the individual neurons in the brain, nor their synaptic patterns. It was intended to demonstrate that the problem of simulating a biological brain could be scaled to very large supercomputer platforms.[102][103]

There are a number of reasons the cat brain is a goal of computer simulations. Cats are familiar and easily-kept animals, so the physiology of cats has been particularly well studied. The physical structures of human brains and cat brains are very similar.[14] Cats, like humans, have binocular vision that gives them depth perception.[104] Building artificial mammal brains requires ever more powerful computers as the brain gets more complex, from the mouse brain, to the rat brain (in 2007), to the cat brain, and ultimately to the human brain. Building artificial mammal brains advances the research of both neuroscience and artificial intelligence, but also leads to questions of the definition of sentient and conscious life forms, and to the ethics of artificial consciousness and the ethics of artificial intelligence.[105]

See also[edit]


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