Dogs are not only able to distinguish tone and content from commands: their brains seem to process both on the same levels as humans.

Dogs understand not only how we talk to them, but also what they are told. This has been proven by a sophisticated series of experiments, the results of which were already published back 2016 in the journal “Science” by scientists led by Attila Andics of the Hungarian Eötvös Lornd University.

According to this, our four-legged friends not only recognize by the tone what masters or mistresses want from them, but also grasp the meaning of individual words such as “fass” or “seat” in themselves – even if they are performed with a monotonous voice. But this is not the only commonality that unites humans and dogs in terms of language comprehension. Apparently, the tone and content in the brains of the animals are also processed at similar levels as in humans. This is now shown by a follow-up experiment, which the team around Andics reports on in the journal “Scientific Reports”.

The researchers again trained their experimental dogs with various praise phrases (“Good boy!”, “Well done!”) as well as neutral expressions (“as if”, “despite”) – sometimes in a neutral, sometimes well-intentioned voice. At the same time, they used functional magnetic resonance imaging (fMRI) to investigate what was happening in the animals’ heads. Andics and his colleagues were able to observe that the brains of the animals process word content and intonation in different hemispheres. Now, however, they also discovered that the hierarchy of language processing also coincided with that in the human brain: As in humans, subcortical areas first recognized the tone of the spoken words. On the other hand, the decoding of the content was more likely to be used by downstream cortical areas.

“Although language processing is unique in humans in many ways, this study reveals exciting similarities between us and a species without its own language,” says Attila Andics. The hierarchical form of language processing, which has now also been discovered in dogs, is probably based on a basic working principle of the brain: For example, it is already known from numerous other areas that emotionally charged stimuli are more likely to be detected at the lower processing levels, while more complex information also requires more complex processing steps in the brain.