As any dog lover will know, humans and dogs can have an undeniable rapport. We've always attributed it to pooches being man's best friend, but now, science is on our side: turns out, they're just like us.
How so? Brain scans of both humans and dogs reveal that we process vocal sounds in the same way - whether it's talking, giggling, or yes, even barking. Based on the results of the study, the voice processing areas in dog brains appear to be located in the same region as the voice processing area in human brains, and results suggest that the vocal processing center evolved just once, over 100 million years ago, when humans and canines are last believed to have shared an ancestor.
Published in Current Biology, the study was headed up by researchers from Hungary's Eötvös Loránd University, with comparative ethnologist Attila Andics of the MTA-ELTE Comparative Ethnology Research Group at the helm. Also instrumental in the study was his colleague Ádám Miklósi, a recognized authority on canine intelligence and behavior.
"What makes us really excited now is that we've discovered these voice areas in the dog brain," said Andics. "It's not only dogs and humans. We probably share this function with many other mammals." He continued: "Dogs and humans share a similar social environment. Our findings suggest that they also use similar brain mechanisms to process social information."
While animals are typically sedated prior to brain scans, Andics and his team were able to train 11 dogs to sit still for long enough - allowing them to scan the pups while they were conscious. Comparing the results of the experiment to the data gleaned from the same test on 22 human participants, the research team noticed that brain activity spiked in response to the same stimuli, and in the same region. The study's participants - human and canine alike - listened to nearly 200 different sounds as their brain activity was tracked.
Perhaps most tellingly, dogs didn't just respond to sounds, but to emotive ones - just as their human counterparts did. And, while the name of the game was sound recognition, the sounds emitted by dogs were also analyzed, lending weight to the theory that dogs, just like humans, express sentiment through sound. Barks were lower and more drawn out when the dogs were distressed, and shorter and higher-pitched when the dogs were pleased. "There are these acoustic rules that convey emotional information, and they seem to be common to species," said Andics.
With the same physical mechanics of processing voice recognition and the same ways of expressing emotion, it's little wonder that humans and dogs have had such a lasting affinity for one another. Andics and his team hope to investigate further in a bid to further understand the intricacies of human communication.
