Some dogs become excited as soon as they hear the word, “squirrel”, but is the dog really responding to the actual word – or the way you say it?
Scientists have debated how much dogs actually understand – and (for instance) whether they really know what the word “squirrel” means, or just think: “Something’s happening!”
Now a new study has used brain scans to find out exactly what is happening inside your dog’s head when you talk to it – using dogs trained to sit still inside MRI scanners.
Lead author Ashley Prichard of Emory’s Department of Psychology said: “Many dog owners think that their dogs know what some words mean, but there really isn’t much scientific evidence to support that”.
“We wanted to get data from the dogs themselves – not just owner reports.”
The researchers scanned dog’s brains while they looked at toys and their owners said the toy’s names – and believe that they do identify words, not just tone of voice.
Emory neuroscientist Gregory Berns said: “We know that dogs have the capacity to process at least some aspects of human language since they can learn to follow verbal commands”.
“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”.
Researchers trained dogs to voluntarily enter a functional magnetic resonance imaging (fMRI) scanner and remain motionless during scanning, without restraint or sedation.
Twelve dogs of varying breeds were trained for months by their owners to retrieve two different objects, based on the objects’ names.
During one experiment, the trained dog lay in the fMRI scanner while the dog’s owner stood directly in front of the dog at the opening of the machine and said the names of the dog’s toys at set intervals, then showed the dog the corresponding toys.
Eddie, a golden retriever-Labrador mix, for instance, heard his owner say the words “piggy” or “monkey”, then his owner held up the matching toy.
As a control, the owner then spoke gibberish words, such as “bobbu” and then held up random objects such as a hat or a doll.
The results showed greater activation in auditory regions of the brain when confronted with something new.
Pritchard said: “We expected to see that dogs neurally discriminate between words that they know and words that they don’t”.
“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 believe it may be because the dogs want to understand the new words to please their owners.
Berns said: “Dogs ultimately want to please their owners, and perhaps also receive praise or food”.