Most dog owners are convinced that their four-legged friends know exactly what they mean when they use certain words like sit, stay, or treat. However, researchers have always wondered whether canines really understand human speech or if they rely on other clues to deduce the meaning. For example, does the word “fetch” conjure up an image of a stick or ball in the dog’s mind, or does the pooch retrieve the object based on cues such as the owner’s tone or gesture? A new study by scientists at Atlanta’s Emory University seems to indicate that “man’s best friend” is not faking it – he/she does indeed know what the owner is saying.
“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,” said Ashley Prichard, a Ph.D. at Emory’s Department of Psychology and the study’s first author.
The researchers began by asking the owners of twelve dogs of various breeds to train their pets to identify two toys with different textures - such as a stuffed animal and a ball - by name. Once the dogs had mastered the task, they took turns inside a functional magnetic resonance imaging scanner (fMRI). The owners then tested their pooch’s language prowess by first calling out the names of the toys they had been trained to recognize and then saying meaningless words such as “bobbu” and “bodmick” while holding up random objects the dogs hadn’t seen before.
The fMRI scans revealed that the regions of the dogs’ brains responsible for auditory processing showed different brain patterns when they heard words they were familiar with, compared with the ones they had never encountered before. While not enough to prove that the dogs were picturing their toys when they heard the word, it did indicate some sort of recognition. The researchers believe this is an important step forward in understanding how dogs process language.
Even more intriguing was that the dog’s brains showed a higher level of neural activity at the sound of unknown words. This is the exact opposite of what happens in human brains, which get more active at the sound of familiar words. The researchers hypothesize the dogs may be perking up at the sound of new words to try to understand them in the hopes of delighting their masters. "Dogs ultimately want to please their owners, and perhaps also receive praise or food," says Emory neuroscientist Gregory Burns, senior author of the study.
However, though your pet may understand human speech, the scientists recommend using visual and scent cues for training. “When people want to teach their dog a trick, they often use a verbal command because that’s what we humans prefer,” Prichard says. “From the dog’s perspective, however, a visual command might be more effective, helping the dog learn the trick faster.”
Resources: cbsnews.com, gizmondo.com, fmri.org, earthsky.org