Posted Date: March 24, 2014
A study shows a similarity between the way dogs and humans react to voices. By Claudia Bensimoun
Until recently, little was known about how dogs react to voices, and if they reacted in the same way that humans do. By studying 11 dogs that were exposed to 200 different sounds, Dr. Attila Andics, from the Comparative Ethology Research Group at the Hungarian Academy of Science at Eotvos Lorand University in Budapest compared how those dogs processed sounds to the results of the same tests done on 22 human volunteers.
A recent study by Dr. Andics has established that a dog's brain reacts to voices in the same way that the human brain does, conveying that perhaps our furry best friends process emotion in a similar manner to humans. Dr. Andics and his team placed dogs in an MRI scanner to observe how dogs and humans process different sounds. The researchers wanted to find out how much different the process was between dogs and humans. It's no surprise that the human brain is especially tuned into voices, so why should dogs be any different?
Until now, not much was known about how dogs process voices. "We think dogs and humans have a very similar mechanism to process emotional information," explains Dr. Andics. Eleven dogs participated in this study, and all the dogs had to undergo some training. "There were 12 sessions of preparatory training, then seven sessions in the scanner room, [and] then these dogs were able to lie motionless for as long as eight minutes. Once they were trained, they were so happy, I wouldn't have believed it if I didn't see it. We used positive reinforcement strategies, [with] lots of praise, added Dr. Andics.
The researchers found that a similar region in both human and animal brains, the temporal pole (which is the most anterior region of the temporal lobe), was stimulated when both the animals and people heard people talking. "We do know there are voice areas in humans, areas that respond more strongly to human sounds than any other types of sounds. The location (of the activity) in the dog brain is very similar to where we found it in the human brain. The fact that we found these areas exist at all in the dog brain at all is a surprise; it is the first time we have seen this in a non-primate."
The researchers found that emotional sounds such as crying and laughter had a similar pattern of activity, where the area close to the primary auditory cortex lit up in both dogs and people. Furthermore, emotionally charged vocalizations like whimpering or aggressive barking resulted in similar reactions in all volunteers. "We know very well that dogs are very good at tuning into the feelings of their owners, and we know a good dog owner can detect emotional changes in his dog, but we now begin to understand why this can be," adds Dr. Andics. Still, dogs tended to respond more to canine sounds; their reactions were less strong when it came to human sounds. It was also evident that dogs were less able to distinguish between environmental sounds and vocal noises compared with humans.
Professor Sophie Scott, from the Institute of Cognitive Neuroscience at the University College, London explains that "finding something like this in a primate brain isn't too surprising, but it is quite something to demonstrate it in dogs. Dogs are a very interesting animal to look at; we have selected for a lot of traits in dogs that have made them very amenable to humans. Some studies have shown they understand a lot of words and they understand intentionality (pointing). It would be interesting to see the animal's response to words rather than just sounds. When we cry and laugh, they are much more like animal calls and this might be causing the response. A step further would be if they had gone in and shown sensitivity to words in the language their owner's speak," explains Professor Scott.
Claudia Bensimoun is a freelance writer in West Palm Beach.