Dogs can distinguish between human languages and display different patterns of activity in a known and an unknown language, Hungarian researchers found, after playing excerpts from the story The Little Prince in Spanish and Hungarian to a group of 18 canines and examining how their dogs reacted.
The research carried out by the Eötvös University of Hungary, and published in NeuroImage, is, according to its authors, the first demonstration that a non-human brain can differentiate between 2 languages.
The experts took brain images of the 18 dogs while they listened to passages of The Little Prince in Spanish and Hungarian, with which they also saw that the older the dog, the better its brain distinguished between the known and the unknown language.
Kun-kun: the “Mexican” dog
The origin of the research was the dog Kun-kun, of the main author of the study Laura Cuaya, who after years living in Mexico, where the animal had only heard Spanish, moved to Hungary. “I wondered if Kun-kun had noticed that people in Budapest spoke another language,” since people, even pre-verbal babies, are known to tell the difference, she said.
A group of 18 dogs, including the researcher’s, were trained to remain motionless in a brain scanner where they listened to the reading fragments in the 2 languages. All the dogs had heard only 1 of the 2 languages from their owners, so they were able to compare a very familiar language with a completely unfamiliar one. The language-specific patterns were found in a brain region called the secondary auditory cortex, the study adds.
Dogs could pick up auditory regularities of human language
“Each language is characterized by a series of auditory regularities. Our findings suggest that, during their life with humans, dogs capture the auditory regularities of the language to which they are exposed”, explained Raúl Hernández-Pérez, other signatories of the study.
Knowing that a non-human brain can distinguish between 2 languages ”is exciting”, he commented, because it reveals that the ability to learn about the regularities of a language is not uniquely human, although it is not yet known whether it is a specialty of dogs or exists in other species.
Dogs can distinguish between different human languages
It is the first demonstration that a non-human brain can differentiate 2 languages.
Did dogs develop sensitivity for thousands of years of coexistence with humans?
It is possible, according to another of the authors, Attila Andics, that “the brain changes produced by the tens of thousands of years that dogs have lived with humans have made them better listeners of language, but this is not necessarily the case”, so that will still have to be found out.
In addition to the read excerpts from The Little Prince, the team had the animals listen to scrambled versions of those same passages, which sound “completely unnatural,” Hernández-Pérez said, to see if they could detect the difference between speech and non-speech.
By comparing brain responses, the researchers found distinct patterns of activity in the dogs’ primary auditory cortex, a distinction that held regardless of whether the stimuli came from the familiar or unfamiliar language.
“The brain of dogs, like that of humans, can distinguish between speech and non-speech. But the mechanism underlying this speech detection ability may be different from that of speech sensitivity in humans”, he explained. While human brains are “especially attuned to speech”, dogs’ brains may detect “just the naturalness of sound”.
