Just like people, some dogs take longer to learn new tricks than others. But new research suggests that this should not come as a surprise; a dog's intelligence is structurally comparable to that of humans and can be measured in a similar way.
Given that dogs experience some key features of dementia, the study authors say understanding the cognitive abilities of "man's best friend" may help us understand what causes the disease in humans.
Dr. Rosalind Arden, a research associate at the London School of Economics and Political Science in the UK, and colleagues publish their findings in the journal Intelligence.
For their study, the researchers created a prototype IQ test, which they used to assess the intelligence of 68 working border collies.
The test assessed the dogs' navigational skills, monitoring the length of time it took for them to retrieve some food that was hidden behind various barriers. It also assessed whether they could differentiate between different food quantities and monitored their ability to follow a human hand gesture, which involved a person pointing toward an object.
It took just under 1 hour to test each dog, which the researchers say is how long it normally takes a person to complete an IQ test.
Dogs could aid understanding between intelligence and health
The researchers explain that when IQ is tested in humans, performance tends to be similar across a variety of cognitive tasks; individuals who perform well in one task often do well in others.
This same pattern was identified among the dogs. The team found that the dogs that performed well on one test performed well on the other tests. Additionally, they found that dogs that completed the tests more quickly tended to perform them more accurately.
Dr. Arden says the results indicate problem-solving abilities vary from dog to dog, just as they do in humans. She notes that this is a significant finding because, generally, humans who are more intelligent tend to be healthier and live longer.
"So if, as our research suggests, dog intelligence is structured similarly to ours, studying a species that doesn't smoke, drink, use recreational drugs and does not have large differences in education and income, may help us understand this link between intelligence and health better," adds Dr. Arden.
And the health implications of these findings may reach even further. Dr. Arden says:
"Dogs are one of the few animals that reproduce many of the key features of dementia, so understanding their cognitive abilities could be valuable in helping us to understand the causes of this disorder in humans and possibly test treatments for it."
While the research is in its early stages, the team says they hope to create a faster, more accurate IQ test for dogs.
"Such a test could rapidly improve our understanding of the connection between dog intelligence, health, even lifespan, and be the foundation of 'dognitive epidemiology,'" says study coauthor Dr. Mark Adams, of the UK's University of Edinburgh.
"Dogs are excellent for this kind of work because they are willing to participate and seem to enjoy taking part."
Last month, Medical News Today reported on a study that suggested dogs can recognize human emotions by drawing on different sensory information - an ability that had only previously been identified in humans and primates.