Ever tried to trick your dog with a cheerful tone but non-sense words? Chances are you dog didn't buy it. Unsurprising to those of us who live with dogs, a new study shows us canines process language in a similar fashion to humans!
When dogs hear speech, he explains, they seem to separate the meaning of words from the intonation, and each aspect of speech is analyzed independently. The left hemisphere of the brain processes meaning, while intonation is analyzed in the right hemisphere.
All the dogs in the study were willing volunteers and were trained to lie still in the scanner using a training method developed by Marta Gacsi. The dogs could get up and leave the machine whenever they wanted. But it was clear to the dogs that their human companions loved it when they did this very easy task.
"They are really happy to participate," says Andics. "The difficult aspect of the training was to convince dogs that 'motionless' means really motionless. They can't move more than 3 millimeters in any direction, otherwise we have to throw out all of the data."
He says most dog owners have experimented with trying to "trick" their dogs by saying nonsense words in a cheerful, happy tone of voice. "I think the big difference here is that they only heard us, they didn't see us," says Andics, because the dogs were inside the machine. "Here, the only information they had was the speech signal. What we saw is that for praise to be processed as a reward, when there is no other supporting information, both word meaning and intonation have to fit."
And while this study reveals something about dogs, he believes it also says something important about what it means to be human.
"Humans seem to be the only species which uses words and intonation for communicating emotions, feelings, inner states," he says. "To find that dogs have a very similar neural mechanism to tell apart meaningful words from meaningless sound sequences is, I think, really amazing."