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Cat intelligence is the capacity of the domesticated cat to learn, solve problems, and adapt to its environment. Researchwhich? 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
- 1 Brain
- 2 Intelligence
- 3 Memory
- 4 Diseases may affect memory
- 5 Intelligence by breed
- 6 Artificial intelligence
- 7 See also
- 8 References
- 9 Further reading
- 10 External links
The brain of the domesticated cat is about 5 centimeters (2 inches) long and weighs 25–30 grams (0.9 to 1.1 ounces).12 If a typical cat is taken to be 60 cm long (23.6 inches) with a weight of 3.3 kg (7.28 lbs.), 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 1973,34 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 – 7.8.13 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 numberquantify of experimentswhich?. 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.7891011
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 A theoretical cat weighing 3,500 grams has a cerebellum weighing 5.3 grams, 0.17% of the total weight.13
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 cortices15 with similar lobes.16
The number of cortical neurons contained in the brain of the cat is reported to be 763 million.17 Area 1718 of the visual cortex was found to contain about 51,400 neurons per mm3.1920 Both human and feline brains are gyrencephalic, i.e., they have a surface folding.2122
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 cat2425 constituting a hypothalamus,26 epithalamus, ventral and dorsal parts27 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 for2930). 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,3334 and have flexibility of cerebral encoding from visual information, adaptability corresponding to changing environmental stimuli.35
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),3839 corpus callosum,4041 anterior commisure,42 pineal gland,43 caudate nucleus, septal nuclei and midbrain.44
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For the optimum health and functioning454647 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
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 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 The number of cortical neurons in the cat brain was calculated as 300 million. Compared to mammalian species this number was eleven-fourteenth in total.152
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.5455 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
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.6162
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
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 speculationby whom? that, just like people, short term memory is more affected by aging. However, research says that adult cats have a memory span of 16 hours compared to only 5 hours in adult dogs especially when it benefits the cat directly.citation needed
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
Cat intelligence study is mostly from consideration of the domesticated cat. Evidence of possible domestication of Felis silvestris dated to 3700 B.C. was found in 2007.64 The process of domestication has allowed for closer observation of cat behaviour and in the increased incidence of interspecies communication,6566 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 identified6768 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.6768 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.69
The intelligence of the cat is believed to be largely dependent upon its inter-species relationscitation 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.70 This scavenging behaviour7172 would only have produced slow changes in evolutionary terms. Such changes are comparable to the changes to the brain73 of early primitive hominids who co-existed with primitive cats, like Machairodontinae, Megantereon and Homotherium, and adapted to savannah conditions.64747576
Considering the fossil-based family tree of placental mammals77 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
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."8081 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.8384 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.868788 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 catclarification needed,8990 P. leo, and P. tigris.
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
Ranking the intelligence of cats by breed is popular among pet owners, veterinarians and others, but the practice tends to run into difficulties.citation needed In general, the subject of cat intelligence rankings tends to be subjective.citation needed Cat breeder Norman Auspitz states the following:relevant?
As a rule, people seem to think the more active breeds have higher intelligence than the less active breeds. I will tell you that in feline agility, all breeds have done very well or very poorly as the case may be.. Having said that, there is no certified measure of cat intelligence and this general rule may be very anthropomorphic... until there is a credible definition of what might be meant by cat intelligence and a way to measure it, any comment anyone will make about the subject is, at best, speculation.93
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,94 animal integrity is cited a reason that genetic transformation of animals should not proceed.959697
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,9899 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 supercomputer100 containing 24,576 processors.101102 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.103104
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 structure of human brains and cat brains are very similar.14 Cats, like humans, have binocular vision that gives them depth perception.105 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.106
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