Just ask your dog “do you want to go for a walk?” You’ll probably have him or her leaping in the air, running to get the leash or scratching enthusiastically at the door. That kind of response makes you think that there’s no doubt your dog understands the meaning behind the words you use. However, not to burst any dog-human bubbles, but new research indicates that may not be so.
Scientists at Emory University recently conducted a study using brain imaging to explore how our “best friends” process words that they have been taught to associate with objects. The study was published in Frontiers in Neuroscience.
The researchers found that dogs have “at least a rudimentary neural representation of meaning for words they have been taught, differentiating words they have heard before from those they have not.” However, there isn’t much scientific evidence to support the belief that dogs know what some words mean.
“We know that dogs have the capacity to process at least some aspects of human language since they can learn to follow verbal commands,” said Emory neuroscientist Gregory Berns, senior author of the study. “Previous research, however, suggests dogs may rely on many other cues to follow a verbal command, such as gaze, gestures and even emotional expressions from their owners.”
The study focused on questions surrounding the brain mechanisms dogs use to differentiate between words, or even what constitutes a word to a dog. Twelve dogs of different breeds participated in the study, with each receiving training at home for several months before the research. Each dog had a set of two objects. One object had a soft texture, such as a stuffed animal; the other was of a different texture such as rubber to facilitate distinction between the two. Training was considered complete when a dog showed that it could discriminate between the two objects by consistently fetching the one requested by the owner when presented with both of the objects.
Using an fMRI scanner to probe auditory discriminations, the researchers took the two different objects and examined how the dogs responded when their owners held up a toy and used its actual name, such as Piggy or Monkey, or used a gibberish word such as “bobbu” then held up a novel object like a hat or doll.
The results showed greater activation to the novel words in auditory regions of the brain compared to the trained words.
“We expected to see that dogs neurally discriminate between words that they know and words that they don’t,” said Ashley Prichard, a PhD candidate in Emory’s Department of Psychology and first author of the study. “What’s surprising is that the result is opposite to that of research on humans — people typically show greater neural activation for known words than novel words.”
The researchers hypothesize that the dogs may show greater neural activation to a novel word because they sense their owners want them to understand what they are saying. In aiming to please, the dogs are trying to understand.
So your dog may hear you but may not necessarily understand what you are saying. That’s why researchers concluded that a visual or scent command might be more effective to help your dog learn than a verbal one.