Is your dog bilingual? A new study suggests their brains can tell languages apart

Imagine you're moving to a new country on the other side of the world.

Besides the geographical and cultural changes, you will find a key difference will be the language. But will your pets notice the difference?

It was a question that nagged at Laura Cuaya, a brain researcher at the Neuroethology of Communication Lab at at Eötvös Loránd University in Budapest.

"When I moved from Mexico to Hungary to start my post-doc research, all was new for me. Obviously, here, people in Budapest speak Hungarian. So you've had a different language, completely different for me," she said.

The language was also new to her two dogs: Kun Kun and Odín.

"People are super friendly with their dogs [in Budapest]. And my dogs, they are interested in interacting with people," Cuaya said. "But I wonder, did they also notice people here ... spoke a different language?"

Cuaya set out to find the answer. She and her colleagues designed an experiment with 18 volunteer dogs — including her two border collies — to see if they could differentiate between two languages. Kun Kun and Odín were used to hearing Spanish; the other dogs Hungarian.

The dogs sat still within an MRI machine, while listening to an excerpt from the story The Little Prince. They heard one version in Spanish, and another in Hungarian. Then the scientists analyzed the dogs' brain activity.

Attila Andics leads the lab where the study took place and said researchers were looking for brain regions that showed a different activity pattern for one language versus the other.

"And we found a brain region — the secondary auditory cortex, which is a higher level processing region in the auditory hierarchy — which showed a different activity pattern for the familiar language and for the unfamiliar language," Andics said.

"This activity pattern difference to the two languages suggests that dogs' brain can differentiate between these two languages. In terms of brain imaging studies, this study is the very first one which showed that a non-human species brain can discriminate between languages."

They also found that older dogs brains' showed bigger differences in brain activity between the two languages, perhaps because older dogs have more experience listening to human language.

Their findings were published this week in the journal NeuroImage.

Amritha Mallikarjun is a researcher at the Penn Vet Working Dog Center in Philadelphia. She wasn't involved in this study, but has been working on similar research about dogs and language.

"I think it is a very exciting study because it shows that the ability to grasp the sounds and rhythms of a familiar language is something accessible to non-humans," she said.

And while this work relied on brain imaging, Mallikarjun said it would be worth investigating whether dogs could differentiate between languages in behavioral studies, too.

"Whether they would behaviorally show a difference between Spanish and Hungarian, or whether this is something more subtle ... because often with neural studies, you can find differences that don't play out in the behavior."

Now, the dogs in the Hungarian study were trained not to move during the sessions, so the scientists could focus on the brain images and not their physical reactions.

But Andics said you should be able to try a version of this test at home, too.

"Start talking to your dog in a language they have never heard," he said. "They will probably look surprised."

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