Dogs may be able to understand human speech

Your dogs may understand more than you give them credit for. A study conducted by researchers from Hungary has found that dogs can understand the meaning and intonation of words using brain regions similar to those that humans use.

There are two main tools humans can use to convey meaning and analyze speech — lexicon and intonation. Words are the building blocks of human language and intonation is a way that information can be understood through emotional content of a sound.

For instance, in human speech patterns, praise tends to be conveyed with higher and varying pitches. When processing speech, humans can use both lexical and intonational cues to arrive at a complete understanding of the content being conveyed.

It is no surprise that dogs have an awareness of human language and speech. Previous studies have observed that domesticated dogs can understand humans better than their wolf counterparts, match objects to words and learn different elements of grammar.

However, these new findings, published in the journal Science, take a look inside the canine brain using an imaging machine. Using this technique, researchers found that dogs are more similar to humans than previously thought — not only do they process vocabulary and intonation in separate areas of the brain, but they do so in the in the same regions as humans.

Researchers from the Eötvös Loránd University (ELTE) in Budapest, Hungary recruited 13 dogs, mostly golden retrievers and border collies. They were trained to lay completely still in an fMRI machine for several minutes. The dogs were unrestrained and could leave the machine whenever they wished. Since they were inside the fMRI machine, they could not see the trainers and researchers.

During the experiment, the dogs were exposed to recordings of the trainers’ voices, which contained multiple combinations of vocabulary and intonation where the trainer spoke different words of praise and neutral words in Hungarian.

Words of praise included common phrases used by dog owners such as “good boy,” “well done” and “clever.” Neutral words included words that the researchers believed were meaningless to the dogs, such as “yet,” “however” and “nevertheless.” Both praise words and neutral words were said in positive and neutral tones.

The researchers found that areas in the left hemisphere of dog’s brains react to vocabulary while areas of the right hemisphere react to intonation. A word associated with praise said in a positive tone activated the reward system of a dog’s brain. All other conditions resulted in less activity, including both a praise word said in a neutral tone and a neutral word said in a positive tone garnered the same neural response.

This shows that dogs are not only able to differentiate vocabulary and intonation but are also able to combine the two and correctly interpret what the words really mean. The researchers hope that these findings will help make cooperation and communication between humans and dogs more efficient.

While these results reveal the way dogs process and analyze human language and speech, the findings also shed light onto the way human understanding of speech could have developed. It suggests that the ability to process meaning and emotion separately and then analyze them together to understand speech could have evolved in non-primates long before humans even began to speak.

The researchers also believe that their findings could shed light onto what it really means to be human.

“Humans seem to be the only species which uses words and intonation for communicating emotions, feelings, inner states,” Attila Andics, ELTE neuroscientist and first author of the study, said in an interview with NPR. “To find that dogs have a very similar neural mechanism to tell apart meaningful words from meaningless sound sequences is, I think, really amazing.”