Did you know that dogs can not only hear you talk and understand certain things you tell them based on the way you structure your vowels and consonants, but also react to features such as your tone of voice, emotions and even gender? That’s what scientists analyzing a variety of ways how dogs hear people are telling us today.
The first evidence has emerged from a recent study, demonstrating that dogs do in fact perceive a load of different, more complex human speech components from all the ways we communicate with our pets, including emotional tone.
Over the years, many dog owners and dog experts have suspected this to be true (videos of dogs reacting to humans barking going viral probably helped), but it’s only now that science is starting to provide some evidence on how dogs hear people. The results of the study support an idea that not only do canines pay attention to the way sentences are said, but also to what exactly is being said, which is quite different from what we have discussed previously. From a neuroscientifical standpoint, this is very similar to the way our human brain takes on communication with the likes of our own species, based on a recent report published in the Cell Press journal Current Biology .
According to study’s co-author Victoria Ratcliffe, these new findings are still in their early stages, and they do not yet prove that canines are able to completely understand all of our emotional tones and aspects of speech, but they do pay attention to that part of expression.
“Although we cannot say how much or in what way dogs understand information in speech from our study, we can say that dogs react to both verbal and speaker-related information and that these components appear to be processed in different areas of the dog’s brain,” says Ratcliffe of the School of Psychology at the University of Sussex.
Interested to see how dogs hear people and react to human speech, and understand more about orienting asymmetries in canine’s response to it? Here’s a video with Victoria Ratcliffe explaining the process:
What researchers have found
Scientists have already knew that dogs have hemispheric biases (right brain and left) which are always engaged for the perception of vocalized sounds produced by other dogs. Therefore, researchers of this study concluded that the most logical next step in understanding how dogs hear people would be to analyze canines’ biases towards the information transmitted by humans, and whether a same response can be achieved.
The team of researchers have brought around 250 domesticated dogs to their lab, all kinds of random breeds. Speakers have been placed on every dog’s head to track how they will process sounds. As shown in the video, left brain hemisphere is responsible for processing sounds that dogs hear closer to their right ear, and vice versa. Thus when pets turned their head to the right, it meant that left hemisphere of dog’s brain has been engaged.
“The input from each ear is mainly transmitted to the opposite hemisphere of the brain. If one hemisphere is more specialized in processing certain information in the sound, then that information is perceived as coming from the opposite ear,” explains Ratcliffe.
More interestingly, scientists have also observed certain biases in most dogs’ responses to certain subtleties of human speech. For example, after dogs heard a familiar command with obvious meaningful components, their left hemisphere would take on the processing bias, but when the tone of speech cues have been exaggerated by the speaker, dogs showed an obvious right brain hemisphere bias.
“This is particularly interesting because our results suggest that the processing of speech components in the dog’s brain is divided between the two hemispheres in a way that is actually very similar to the way it is separated in the human brain,” says David Reby, study’s co-author and Ratcliffe’s supervisor.
While this does not indicated that our canine companions can understand human language, or that we definitely know how dogs hear people, this study’s results suggest that dogs are definitely paying attention to not only who is addressing them or how the things are said, but also to what is being said. No doubt more research into subject is necessary to draw more accurate conclusions, but this comes as good news for majority of all of us – dog loving homo sapiens who cannot spend a day without attempting to talk to their pets.
- Ratcliffe et al. Orienting asymmetries in dogs’ responses to different communicatory components of human speech. Current Biology, November 2014. 15;24(24):2908-12. doi: 10.1016/j.cub.2014.10.030