In search of 'dognition'

Can dogs think? And if they have some level of cognition, what the heck are they thinking about? Researchers at two centers, the Duke Canine Cognition Center and Emory University's Center for Neuropolicy, are trying to answer those questions. They are finding-to no veterinary professional's surprise-that dogs do indeed have a high degree of social and emotional intelligence.

Not training but reasoning

At the Duke Canine Cognition Center, the mission is to discern the way dogs understand the world, says Evan MacLean, PhD, senior research scientist and co-director. The center, which is in Duke University's Department of Evolutionary Anthropology, seeks to understand the similarities and differences in dog and human psychology, as well as how dog psychology compares with that of other species.

Hide and go seek. At the Duke Canine Cognition Center, a dog watches as a reward is hidden in a memory task; 20 to 30 seconds later, the dog will have the opportunity to search in one of the three locations. (Photo courtesy of Dr. Evan MacLean)

Each dog as a unique snowflake. “It turns out that dogs behave quite similarly to human children,” says MacLean. “There are many aspects of the dog mind that are similar to the human mind.”

MacLean says his team is trying not just to describe dog psychology-how dogs do this or that-but to ask questions about individual differences in dog cognition, behavior and psychology. In other words, what makes the minds of individual dogs different; what are their different cognitive strengths and weaknesses? 

Center researchers want to use what they're learning about canine cognition to help predict which dogs will be good at which types of work. The center collaborates with the U.S. Office of Naval Research and with assistance-dog agencies to help them identify the cognitive characteristics of dogs that may be most successful in their programs. 

MacLean says the researchers are interested not in what one can train a dog to do, but in how dogs spontaneously solve problems. “We look at dogs with no training and try to understand how they reason and figure things out in unique situations, and in what situations dogs are clever and insightful, and in which situations they're not so bright,” MacLean says.

Assimilating subtle social cues. As noted in The Genius of Dogs (Dutton, 2013), written by MacLean's colleagues Brian Hare, PhD, and Vanessa Woods, PhD, some basic cognitive traits show that dogs can interpret signals and understand the communicative intentions of simple human gestures. “We ask questions, without language, in such a way that we don't have to train the dog to solve the problem,” MacLean explains.

For example, in various studies conducted at the center, it's been shown that dogs can figure out the location of a food reward based on social cues alone. In one study, the dogs determine where the food is simply from a person pointing toward the correct location. 

A rewarding gesture. At the Duke Canine Cognition Center, a reward is hidden in one of the two buckets, but the dog doesn't know which. Will she use the pointing gesture to find the food? (Photo courtesy of Dr. Evan MacLean)

“We set up a game where something is hidden underneath one of two buckets,” MacLean says. “The dogs know the reward is in one of the two buckets, but they don't know which one. We give the dogs cues to where the food is. In some cases we use a social cue, as we very subtly look in the direction of one of the two hiding places. We try to see if dogs can use that type of social information. By and large they are very sensitive to a whole range of social cues to which other species aren't.”

The dogs are precluded from using their noses to locate the food. “The containers are a distance of at least a couple of meters from where they are searching,” MacLean explains. “If you let them use their noses, they can eventually work their way to the food. But starting a few meters away, without being able to come close to the containers, they can't very accurately locate it by smell.”

Researchers have also determined that dogs are most likely to follow a human's gaze if the person calls their name before looking in the desired direction. What's more, dogs are able to respond to the gaze of other dogs. For example, a dog will correctly identify one of two locations-the one with the food reward-just by following another dog's gaze.

In another study, food was shown to dogs and then placed within another container and stored out of reach. The dogs were able to correctly identify and communicate where the food treat was contained by barking and looking toward the owner, indicating the dog's recognition of food that had been hidden.

Constant canine observers. Studies show that dogs can observe and then act on human gestures, skills that indicate their domestication and cognitive evolution. Says Hare, “A lot of the initial research on ‘dognition' has focused on communicative abilities. We've seen that dogs are geniuses in their ability to read our gestures. Their skills are similar to what we observe in infants. The mental flexibility of dogs has led other researchers and me to suggest that dogs have a basic appreciation of our communicative intentions. They often use our behavior to infer what we want.”

Building a functional map of the canine brain

Gregory Berns, MD, PhD, director of Emory University's Center for Neuropolicy, describes in his book How Dogs Love Us (New Harvest, 2013) how he and his colleagues have learned about dogs' social and cognitive hierarchy from magnetic resonance imaging (MRI) scans of their brains. Berns' key question: Is it possible to scan a dog's brain and figure out what it's thinking?

Sitting pretty still. Dr. Gregory Berns' own dog Callie in an MRI unit at Emory University's Center for Neuropolicy. (Photo courtesy of Dr. Gregory Berns)

The power of peas versus hotdogs. In what Berns describes as “The Dog Project,” he and his colleagues studied two dogs-a rat terrier and a border collie. They trained the dogs to remain perfectly still while undergoing functional and structural MRI scans. The intent was to gain a sufficient number of MRI images to properly assess the dogs' cognitive activity.

The researchers offered positive rewards such as hot dogs and praise, and they took MRI brain scans to determine dog cognition-or what the dogs were “thinking.” The objective of the work was to compare the dogs' responses to two stimuli: one strong and more favorable (hot dogs), the other weaker and less favorable (peas). Images of the dogs' brains allowed Berns to do a crude analysis of brain activity specifically in the cortex and caudate area.

After analyzing the data, Berns knew roughly which parts of the dogs' brains responded to human hand signals they had learned for peas and hot dogs. But this still didn't necessarily tell him what the dogs were thinking. To determine that, Berns had to interpret patterns of activation based on similar patterns in humans. If the comparison proved correct, Berns could begin to build a functional map of the canine brain. Using the concept of homology, Berns could infer canine thought processes from dogs' human equivalents.

Berns and his colleagues decided that the reward system used in dog training belonged to the caudate section of the brain. When they analyzed reverse inference in the caudate, they found that activity in this region was almost always associated with the expectation of something good. As long as they stuck to the caudate, Berns suggested, they would be safe in interpreting activity in this part of the dog's brain as a signal of a positive feeling. Even a dog's love, they inferred, was associated with caudate activation. 

“I really love hot dogs!” Berns and his colleagues reasoned that since hot dogs were more likeable than peas, caudate activity should be greater for the hand signal for hot dogs than it was for the signal for peas. And, in fact, both dogs showed unmistakable proof of caudate activation for the positive response to hot dogs. From his findings, Berns concluded via fMRI a definitive relationship between a dog's brain response to a positive “like” stimulus and hand signals for the preferred food. 

The dog's caudate activation, as the MRI data indicated, was the first piece of evidence Berns needed to begin to understand the dog's intentions as demonstrated by activity in its brain. Dogs, like humans, Berns notes, “just want to be understood.”

Love does enter through the nose. Berns also explored the olfactory areas of the canine brain and the role scent plays. The most interesting finding, he notes, appeared when Berns and his team divided dog and human scents into subcategories of familiar and unfamiliar. “One and only one activated the caudate brain region: ‘familiar human.' The dog essentially knew who its family was and remembered them,” Berns says.

Researchers have found further evidence for this interpretation in the inferior temporal lobe, the part of the brain associated with memory function. The dogs' inferior temporal lobes were strongly activated by the smell of a familiar human, which further suggests to Berns that dogs remember their human family. 

The mental map starts to take shape. Throughout The Dog Project, Berns and colleagues focused on the dog-human relationship. Even with data from just two dogs, a picture is beginning to emerge. The pattern of activation seen via MRI brain scans suggests that dogs create mental models of human behavior. Those mental models include data of important people in their lives-that is, brain scans indicate that dogs associate positively with people: a scientific indication of dog as man's best friend. 

In essence, The Dog Project found that dogs show social learning and that they care about human intentions as evidenced by their brain scans. “Proof of social cognition of dogs shows that dogs are not just Pavlovian learning machines. It means that dogs are sentient beings,” Berns concludes.

Since his initial studies on the border collie and rat terrier, Berns has done MRI scans on more than 50 dogs, providing further data to the burgeoning field of dognition. The most important thing Berns says he has learned from these studies is that a dog's brain shows evidence of a theory of mind for humans. Dogs apparently make mental models of what humans intend-and also what we think. 

Ed Kane, PhD, is a researcher and consultant in animal nutrition. He is an author and editor on nutrition, physiology and veterinary medicine with a background in horses, pets and livestock. Kane is based in Seattle.