What's at the root of our bond with dogs?
Do dogs see us simply as their food-delivery vehicles, or is there something more substantial underlying the human-dog bond?
Scientists at Emory University set out to answer this very question. Neuroscientist Gregory Berns and his team of researchers at the Dog Project in Emory's psychology department designed an experiment to see if dogs prefer verbal praise to food rewards, or vice versa.
"One theory about dogs is that they are primarily Pavlovian machines. They just want food and their owners are simply the means to get it...Another, more current, view of their behavior is that dogs value human contact in and of itself," said Berns.
In order to conduct the study, the team trained dogs to make associations with specific household items. They trained them to associate a toy truck with a food reward and a toy knight with verbal praise. They used a hairbrush as a control item and trained them to associate it with no reward.
After the team trained the dogs to make the appropriate associations with each items, the dogs were put in a functional magnetic resonance imaging (fMRI) scanner. The scanner recorded each dog's neural activity as it was tested 32 times on each of the three items.
The final phase of the study was a behavioral test. The researchers placed each dog in a Y-shaped maze. The dog's owner sat at one tip of the Y. The other tip of the Y held a bowl of food. Once loose in the maze, a dog that went to its owner first, instead of to the food, received verbal praise. The team repeatedly tested each dog in this manner and recorded its choices.
"Out of the 13 dogs that completed the study, we found that most of them either preferred praise from their owners over food, or they appeared to like both equally," Berns reported.
Only two of the animals tested showed a strong and consistent preference for food over praise.
Moreover, the fMRI results showing the dogs' brain activity related to the item associations were commensurate with the results of their behavioral tests and the choices they made in the Y-shaped maze.
"Dogs are individuals, and their neurological profiles fit the behavioral choices they make," said Berns. "Most of the dogs alternated between food and owner but the dogs with the strongest neural response to praise chose to go to their owners 80 to 90 percent of the time. It shows the importance of social reward and praise to dogs. It may be analogous to how we humans feel when someone praises us."
These results are heartening to pooch owners in that they confirm what most of us already believe about our four-legged friends...they really DO adore us (or at least, most of them do).
If you'd like to read the study, you can do so here.