The next time you have a full-blown conversation with your dog, you can rest assured that, even though he can't respond, he fully understands exactly what you just said.
Many people might have previously believed that canines could only understand humans by our inflection in the way that we speak. However, according to a new study, dogs can actually understand human vocabulary, regardless of our tone of voice.
That means owners can't trick their pooch into thinking something positive when telling them in a sweet and upbeat voice that they are about to go to the vet.
While other studies have found that man's best friend has the intelligence to match objects to words, this new, first-of-its-kind study took a deeper look at the brains of dogs to determine that they process language in the same way humans do.
For the study, researchers in Hungary used a group of 13 dogs of various breeds like German shepherds, golden retrievers and collies that ranged in age from one to 12. The research team played recordings of trainers' voices that featured a wide range of words and both positive and neutral intonations in the way they spoke.
Led by Attila Andics, a researcher at the Eötvös Loránd University in Budapest, the team then used a functional magnetic resonance imaging (fMRI) scanner to analyze the dogs' brain activity as they listened to their trainers' recorded speech.
The researchers found that, just like humans, the dogs used the left hemisphere of their brains to recognize words.
According to the researchers, learning vocabulary "does not appear to be a uniquely human capacity that follows from the emergence of language, but rather a more ancient function that can be exploited to link arbitrary sound sequences to meanings."
The study, which is featured in the Sept. 2 issue of the journal Science, also found that the animals process intonation in speech separately from vocabulary in the right hemisphere of their brain. This means the dogs were able to understand speech regardless if the trainers used a higher pitch that is associated with something positive, even if they were saying something neutral.
As a result of this study, the researchers concluded that dogs use both words and intonation to determine if what their owner is saying to them has reward value.
"This shows … that dogs not only separate what we say from how we say it, but also that they can combine the two for a correct interpretation of what those words really meant," Andics said.
A previous study looked at how dogs understood speech and found that the processing of speech components in the canine brain is split between the right and left hemispheres in a way similar to how it is divided in the human brain.
These studies prove that, when your pooch looks at you with those puppy eyes when you say something mean, he or she may very well have understood exactly what you said.
The ability for dogs to understand vocabulary and tone in the same way humans do may be linked to domestication.