Many people, including myself, think of humans and dogs as completely non-related species, however recent studies have showed that we may be more closely related in some areas than we thought. One of these studies finds that dog and human brains turn out to be surprisingly familiar, at least where communication and emotions are concerned, which may explain why the two species make such great companions.
Human and dog brains are found to process sounds in similar ways, which may allow the two species to understand each other’s emotions. The presence of voice areas in both dog and human brains suggests this region existed in an ancestor of the two species that lived as long ago as 100 million years ago. Scientists predict that it is not probable that the two species evolved these similar brain mechanisms independently, rather that the shared mechanisms can be traced back to the last common ancestor of the two, leading to the theory that the mechanisms evolved before the two split.
In the study, the researchers tested 11 dogs; golden retrievers and border collies, along with 22 people. The dogs and humans were both presented with nearly 200 human and dog produced sounds such as whining, cheerful barking, crying, and laughing. The scientists were able to observe the subjects brain reaction using a functional magnetic resonance imaging (fMRI) scanner. As predicted, the scientists found that the dogs reacted most strongly to the sounds produced by dogs, whereas the humans reacted most strongly to the sounds produced by humans. Along with these results the scientists found that the subjects also responded to the emotions in each other’s sounds. For example, when the participants heard “happy” sounds, in both species, the same part of the brain lit up more than for “unhappy” sounds.
Contrary to the recent studies, it was found that dog and human brains respond extremely differently to non-vocal sounds. For example, in dogs, 48% of their sound-sensitive brain regions responded more strongly to non-vocal sounds than vocal sounds, compared with only 3% of sound-sensitive brain regions in humans. The researchers say the study is a first step in helping understand how our four-legged friends are so good at sensing our feelings.
Another theory that contributes to the similarity of humans and dogs brains is the idea that humans’ yawns are “contagious” to dogs. Researchers note that contagious yawning plays a potential role in communication, social interactions and empathy. Basically, it has to do with social attachment between individuals. In the study it was found that although dogs tend to yawn when they see another person yawning, they respond more to the yawns of their owners than those of a stranger. Along with this, researchers observed that dogs responded less to fake yawns, showing that they have the capacity, like humans, to yawn as a result of other people’s yawns.
Although humans and dogs are not similar to the naked eye whatsoever, the previous in-depth studies have shown that the two species have more in common in brain activity than thought. So next time you notice a change in your dog’s reaction to your displayed emotion, know that they are experiencing similar actions to what you, as a human, personally experience.