Your dog knows when you really mean he’s a good boy—and when you’re giving him empty praise.
On a neurological level, dogs can distinguish between praise and neutral tones just like their owners, Hungarian researchers reported (paywall) on Aug. 29 in the journal Science. Their reward centers only became activated when they heard positive intonation that matched the words they were hearings.
“Dogs not only tell apart what we say and how we say it, but they can also combine the two, for a correct interpretation of what those words really meant,” Attila Andics, an animal behaviorist at Eötvös Loránd University in Budapest and lead author of the paper said in a press release (pdf). “This is very similar to what human brains do.”
For their work, Andics and her team trained 13 dogs to remain motionless in a functional magnetic resonance imaging (fMRI) machine, which measures blood flow. More blood means more oxygen is being delivered to a given area, and implies that region is being used more than usual. They observed the dogs’ brains as the animals listened to human speech. Dogs heard praise in a friendly tone, praise in a neutral tone, and words they hadn’t previously been exposed to with both kinds of intonation.
When the dogs recognized words they were previously familiar with, a part of their brain in the left hemisphere became more activated—similar to the way humans process languages. Additionally, the researchers found that dogs’ reward centers located in both the left and right hemispheres of the brain—the parts of the brain associated with getting treats and being pet—were only activated when they heard praise in a positive tone. “For dogs, a nice praise can very well work as a reward, but it works best if both words and intonation match,” Andics said.
These findings should come with a grain of salt. Functional MRIs don’t always provide full pictures of brain activity, and they’ve been known to produce false positives (paywall), even suggesting that dead salmon had some kind of brain activity (which they don’t). Even short of a mechanical glitch, 13 dogs can hardly speak for the entire population of canines.
Still, this research suggests that dogs and other animals are capable of understanding human language on a slightly deeper level than it may seem. We have a long history of training dogs to respond to auditory commands, and previous research has shown that dogs recognize some of our emotions. Canines may actually combine these two abilities to interpret our words—at least when it comes to praise.