Dog intelligence or dog cognition is the process in
dogs of acquiring, storing in memory, retrieving, combining, comparing,
and using in new situations information and conceptual skills.
Studies have shown that dogs display many behaviors associated
with intelligence. They have advanced memory skills, and are able to
read and react appropriately to human body language such as gesturing
and pointing, and to understand human voice commands. Dogs demonstrate a
theory of mind by engaging in deception.
Evolutionary perspective
Dogs
have often been used in studies of cognition, including research on
perception, awareness, memory, and learning, notably research on classical and operant conditioning.
In the course of this research, behavioral scientists uncovered a
surprising set of social-cognitive abilities in the domestic dog,
abilities that are neither possessed by dogs' closest canine relatives
nor by other highly intelligent mammals such as great apes. Rather,
these skills resemble some of the social-cognitive skills of human
children. This may be an example of Convergent evolution,
which happens when distantly related species independently evolve
similar solutions to the same problems. For example, fish, penguins and
dolphins have each separately evolved flippers as solution to the
problem of moving through the water. With dogs and humans, we may see
psychological convergence; that is, dogs have evolved to be cognitively
more similar to humans than we are to our closest genetic relatives.
However, it is questionable whether the cognitive evolution of
humans and animals may be called "independent". The cognitive capacities
of dogs have inevitably been shaped by millennia of contact with
humans. As a result of this physical and social evolution, many dogs readily respond to social cues common to humans, quickly learn the meaning of words, show cognitive bias and exhibit emotions that seem to reflect those of humans.
Research suggests that domestic dogs may have lost some of their
original cognitive abilities once they joined humans. For example, one
study showed compelling evidence that dingos (Canis dingo)
can outperform domestic dogs in non-social problem-solving experiments.
Another study indicated that after being trained to solve a simple
manipulation task, dogs that are faced with an unsolvable version of the
same problem look at a nearby human, while socialized wolves do not.
Thus, modern domestic dogs seem to use humans to solve some of their
problems for them.
In 2014, a whole genome study of the DNA differences between
wolves and dogs found that dogs did not show a reduced fear response,
they showed greater synaptic plasticity.
Synaptic plasticity is widely believed to be the cellular correlate of
learning and memory, and this change may have altered the learning and
memory abilities of dogs.
Most modern research on dog cognition has focused on pet dogs
living in human homes in developed countries, which is only a small
fraction of the dog population and dogs from other populations may show
different cognitive behaviors. Breed differences possibly could impact on spatial learning and memory abilities.
Studies history
The
first intelligence test for dogs was developed in 1976. It included
measurements of short-term memory, agility, and ability to solve
problems such as detouring to a goal. It also assessed the ability of a
dog to adapt to new conditions and cope with emotionally difficult
situations. The test was administered to 100 dogs and standardized, and
breed norms were developed. Stanley Coren used surveys done by dog obedience judges to rank dog breeds by intelligence and published the results in his book The Intelligence of Dogs.
Perception
Perception
refers to mental processes through which incoming sensory information
is organized and interpreted in order to represent and understand the
environment.
Perception includes such processes as the selection of information
through attention, the organization of sensory information through
grouping, and the identification of events and objects. In the dog,
olfactory information (the sense of smell) is particularly salient
(compared with humans) but the dogs senses also include vision, hearing,
taste, touch and proprioception. There is also evidence that dogs sense
the earth's magnetic field.
One researcher has proposed that dogs perceive the passing of time through the dissipation of smells.
Awareness
The concept of "object permanence"
refers to the ability of an animal to understand that objects continue
to exist even when they have moved outside of their field of view. This
ability is not present at birth, and developmental psychologist Jean Piaget
described six stages in the development of object permanence in human
infants. A similar approach has been used with dogs, and there is
evidence that dogs go through similar stages and reach the advanced
fifth stage by an age of 8 weeks. At this stage they can track
"successive visible displacement" in which the experimenter moves the
object behind multiple screens before leaving it behind the last one. It
is unclear whether dogs reach Stage 6 of Piaget's object permanence
development model.
A study in 2013 indicated that dogs appear to recognize other
dogs regardless of breed, size, or shape, and distinguish them from
other animals.
In 2014, a study using magnetic resonance imaging
demonstrated that voice-response areas exist in the brains of dogs and
that they show a response pattern in the anterior temporal voice areas
that is similar to that in humans.
Social cognition
Social learning: observation and rank
Dogs are capable of learning through simple reinforcement (e.g., classical or operant conditioning), but they also learn by watching humans and other dogs.
One study investigated whether dogs engaged in partnered play
would adjust their behavior to the attention-state of their partner. The
experimenters observed that play signals were only sent when the dog
was holding the attention of its partner. If the partner was distracted,
the dog instead engaged in attention-getting behavior before sending a
play signal.
Puppies learn behaviors quickly by following examples set by experienced dogs.
This form of intelligence is not particular to those tasks dogs have
been bred to perform, but can be generalized to various abstract
problems. For example, Dachshund
puppies were set the problem of pulling a cart by tugging on an
attached piece of ribbon in order to get a reward from inside the cart.
Puppies that watched an experienced dog perform this task learned the
task fifteen times faster than those left to solve the problem on their
own.
The social rank of dogs affects their performance in social
learning situations. In social groups with a clear hierarchy, dominant
individuals are the more influential demonstrators and the knowledge
transfer tends to be unidirectional, from higher rank to lower. In a
problem-solving experiment, dominant dogs generally performed better
than subordinates when they observed a human demonstrator's actions, a
finding that reflects the dominance of the human in dog-human groups.
Subordinate dogs learn best from the dominant dog that is adjacent in
the hierarchy.
Following human cues
Dogs show human-like social cognition in various ways.
For example, dogs can react appropriately to human body language such
as gesturing and pointing, and they also understand human voice
commands.
For example, in one study, puppies were presented with a box, and shown
that, when a handler pressed a lever, a ball would roll out of the box.
The handler then allowed the puppy to play with the ball, making it an
intrinsic reward. The pups were then allowed to interact with the box.
Roughly three quarters of the puppies subsequently touched the lever,
and over half successfully released the ball, compared to only 6% in a
control group that did not watch the human manipulate the lever.
Similarly, dogs may be guided by cues indicating the direction of a human's attention.
In one task a reward was hidden under one of two buckets. The
experimenter then indicated the location of the reward by tapping the
bucket, pointing to the bucket, nodding at the bucket, or simply looking
at the bucket. The dogs followed these signals, performing better than chimpanzees, wolves, and human infants at this task; even puppies with limited exposure to humans performed well.
Dogs can follow the direction of pointing by humans. New Guinea singing dogs
are a half-wild proto-dog endemic to the remote alpine regions of New
Guinea and these can follow human pointing as can Australian dingoes.
These both demonstrate an ability to read human gestures that arose
early in domestication without human selection. Dogs and wolves have
also been shown to follow more complex pointing made with body parts
other than the human arm and hand (e.g. elbow, knee, foot).
Dogs tend to follow hand/arm pointed directions more when combined with
eye signaling as well. In general, dogs seems to use human cues as an
indication on where to go and what to do. Overall, dogs appear to have several cognitive skills necessary to
understand communication as information; however, findings on dogs'
understanding of referentiality and others' mental states are
controversial and it is not clear whether dog themselves communicate
with informative motives.
For canines to perform well on traditional human-guided tasks
(e.g. following the human point) both relevant lifetime experiences with
humans—including socialization to humans during the critical phase for
social development—and opportunities to associate human body parts with
certain outcomes (such as food being provided by humans, a human
throwing or kicking a ball, etc.) are required.
In 2016, a study of water rescue dogs that respond to words or
gestures found that the dogs would respond to the gesture rather than
the verbal command.
Memory
Episodic memory
Dogs have demonstrated episodic-like memory by recalling past events that included the complex actions of humans.
In a 2019 study, a correlation has been shown between the size of the
dog and the functions of memory and self-control, with larger dogs
performing significantly better than smaller dogs in these functions.
However, in the study brain size did not predict a dog's ability to
follow human pointing gestures, nor was it associated with their
inferential and physical reasoning abilities.
Learning and using words
Various
studies have shown that dogs readily learn the names of objects and can
retrieve an item from among many others when given its name. For
example, in 2008, Betsy, a Border Collie,
knew over 340 words by the retrieval test, and she was also able to
connect an object with a photographic image of the object, despite
having seen neither before.
In another study, a dog watched as experimenters handed an object back
and forth to each other while using the object's name in a sentence. The
dog subsequently retrieved the item given its name.
In humans, "fast mapping"
is the ability to form quick and rough hypotheses about the meaning of a
new word after only a single exposure. In 2004, a study with Rico,
a Border Collie, showed he was able to fast map. Rico initially knew
the labels of over 200 items. He inferred the names of novel items by
exclusion, that is, by knowing that the novel item was the one that he
did not already know. Rico correctly retrieved such novel items
immediately and four weeks after the initial exposure. Rico was also
able to interpret phrases such as "fetch the sock" by its component
words (rather than considering its utterance to be a single word). Rico
could also give the sock to a specified person. This performance is
comparable to that of 3-year-old humans.
In 2013, a study documented the learning and memory capabilities
of a border collie, "Chaser", who had learned the names and could
associate by verbal command over 1,000 words at the time of its
publishing. Chaser was documented as capable of learning the names of
new objects "by exclusion", and capable of linking nouns to verbs. It is
argued that central to the understanding of the border collie's
remarkable accomplishments is the dog's breeding background—collies bred
for herding work are uniquely suited for intellectual tasks like word
association which may require the dog to work "at a distance" from their
human companions, and the study credits this dog's selective breeding
in addition to rigorous training for her intellectual prowess.
Emotional intelligence
Studies suggest that dogs feel complex emotions, like jealousy and anticipation. However, behavioral evidence of seemingly human emotions must be interpreted with care. For example, in his 1996 book Good Natured, ethologist Frans de Waal discusses an experiment on guilt and reprimands conducted on a female Siberian Husky.
The dog had the habit of shredding newspapers, and when her owner
returned home to find the shredded papers and scold her she would act
guilty. However, when the owner himself shredded the papers without the
dog's knowledge, the dog "acted just as 'guilty' as when she herself had
created the mess." De Waal concludes that the dog did not display true
guilt as humans understand it, but rather simply the anticipation of
reprimand.
One limitation in the study of emotions in non-human animals, is that they cannot verbalise to express their feelings. However, dogs' emotions can be studied indirectly through cognitive tests, called cognitive bias test, which measure a cognitive bias and allow to make inference about the mood of the animal. Researchers have found that dogs suffering from separation anxiety have a more negative cognitive bias, compared to dogs without separation anxiety. On the other hand, when dogs' separation anxiety is treated with
medications and behaviour therapy, their cognitive bias becomes less
negative than before treatment. Also administration of oxytocin, rather than a placebo, induces a more positive cognitive bias and positive expectation in dogs. It is therefore suggested that the cognitive bias test can be used to
monitor positive emotional states and therefore welfare in dogs.
There is evidence that dogs can discriminate the emotional expressions of human faces.
In addition, they seem to respond to faces in somewhat the same way as
humans. For example, humans tend to gaze at the right side of a person's
face, which may be related to the use of right brain hemisphere for
facial recognition. Research indicates that dogs also fixate the right
side of a human face, but not that of other dogs or other animals. Dogs
are the only non-primate species known to do so.
Problem solving
Sex-specific
dynamics are an important contributor to individual differences in
cognitive performance of pet dogs in repeated problem-solving tasks.
Captive-raised dingoes (Canis dingo) can outperform domestic dogs in non-social problem-solving.
Another study indicated that after undergoing training to solve a
simple manipulation task, dogs faced with an unsolvable version of the
same problem look at the human, whereas socialized wolves do not. Modern domestic dogs use humans to solve their problems for them.
Learning by inference
Dogs have been shown to learn by making inferences in a similar way to children.
Dogs have the ability to train themselves and learn behaviors through interacting and watching other dogs.
Theory of mind
"Theory of mind" is the ability to attribute mental states—beliefs, intents, desires, pretending, knowledge,
etc.—to oneself and others and to understand that others have beliefs,
desires, intentions, and perspectives that are different from one's own. There is some evidence that dogs demonstrate a theory of mind
by engaging in deception. For example, one observer reported that a dog
hid a stolen treat by sitting on it until the rightful owner of the
treat left the room.
Although this could have been accidental, it suggests that the thief
understood that the treat's owner would be unable to find the treat if
it were out of view.
A study found that dogs are able to discriminate an object that a human
partner is looking for based on its relevance for the partner and they
are more keen on indicating an object that is relevant to the partner
compared to an irrelevant one; this suggests that dogs might have a
rudimental version of some of the skills necessary for theory of mind.