A new study at the Emory University of Atlanta says that the scent of a dog's owner activates a part of the dog's brain associated with pleasure.
The research was led by Gregory Berns, director of Emory University's Center for Neuropolicy, and was published in the journal Behavioral Processes, according to RedOrbit. The study included 12 dogs from different breeds that had gone through training to stay still while undergoing an fMRI scan.
While humans and dogs have been developing relationships for 40,000 years, interpreting dogs' barks, tail wags other behaviors still poses a challenge to scientists, National Geographic reported.
"We started the dog project about three years ago to get around this problem that we really don't know what dogs are thinking or what they're experiencing," Berns said.
The dogs were presented with five scents on gauze pads, which were a familiar human, an unfamiliar human, a dog that lived in their neighborhood household, an unfamiliar dog, and their own scent. The researchers found that the scent of a familiar person activated the dogs' caudate nucleus, an area of the brain connected to positive expectations. The discovery suggests that dogs can recognize their owners and that scents of familiar people stay in the dog's mind, National Geographic reported.
The researchers also found that service and therapy dogs who had received more training experienced greater caudate activation for owners and familiar humans than other dogs did, RedOrbit reported.
"It's one thing when you come home and your dog sees you and jumps on you and licks you and knows that good things are about to happen," Berns said. "In our experiment, however, the scent donors were not physically present. That means the canine brain responses were being triggered by something distant in space and time. It shows that dogs' brains have these mental representations of us that persist when we're not there."
Berns said the team will do more research to see if they can use brain-imaging techniques to find dogs that can serve as companion animals for the disabled, RedOrbit reported.
"In addition to serving as companion animals for wounded veterans, dogs play many important roles in military operations," Berns said. "By understanding how dogs' brains work, we hope to find better methods to select and train them for these roles."
