Is affection more valuable than food? At least for most dogs it is!

In line with finding out how strong the relationship between dog and owners is, researchers conducted an experiment.

"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," Gregory Berns, a neuroscientist at Emory University who lead the study, said in a news release.

"Another, more current, view of their behavior is that dogs value human contact in and of itself."

Berns also heads the Dog Project in Emory's Department of Psychology, which is about researching evolutionary questions surrounding dogs.

For the study, the researchers gathered 13 dogs for two sets of experiments.

For the first one, the researchers trained the dogs to associate three objects with three different rewards: a pink toy truck with food; a blue toy knight with verbal praise; and a hairbrush with the absence of a reward.

After 32 trials, most of the dogs proved that they aren't single-minded. Via an fMRI machine, each dog's neural response to each stimulus were measured. Four dogs showed a particularly strong response to the blue toy knight.

In the second experiment, they were trained to familiarize themselves with two sets of maze. The one leads to food while the other to their owner.

"We found that the caudate response of each dog in the first experiment correlated with their choices in the second experiment," Berns says.

"Dogs are individuals and their neurological profiles fit the behavioral choices they make. 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."

Berns said that the findings show how important praise and social rewards among dogs just like how humans feel when they are praised.

A separate study conducted in 2015 provided that first scientific evidence proving that humans and dogs bond emotionally by releasing "love hormones." The more a dog gazes into a human's eyes, the more pleasure and happiness it experiences.