Few dog owners would disagree their dog can instantly recognise the words for ‘walk’, ‘dinner’ or ‘ball’, for example, but a study led by researchers from Hungary’s Eötvös Loránd University wanted to take this recognition a step further, and find out what might be happening in a dog’s brain in respect of name recognition, and if they were reacting to the word’s sound, or if they had a genuine understanding of the word.
Published recently in the journal Current Biology, the study found that when dogs heard certain words, brain activity recordings suggested a matching mental representation in their minds was activated.
Co-first author Marianna Boros, a junior research fellow at the University’s Department of Ethology, said dogs did not only react with learned behaviour to certain words without really understanding their meaning, a memory of the object was activated in the animal’s brain when dogs heard the object’s name.
“It didn’t matter how many object words a dog understood – known words activate mental representations anyway, which suggests this ability is generally present in dogs and not just in some exceptional individuals who know the names of many objects,” she said.
Non-invasive brain imaging was the technique used to measure brain activity in a study that involved 18 dog owners saying words for toys their dogs knew, and then presenting the objects to them. Sometimes the matching toy was presented, while at other times the dogs were presented with a mismatched object.
The brain recording results showed a different pattern in the brain when the dogs were shown a matching object versus a mismatched one. This correlated with similar word understanding tests with individuals who do not speak, like infants, and that are widely accepted as evidence the words are understood.
The researchers said the discovery that dogs as a species may generally have a capacity to understand words in a referential way, just as humans do, may reshape the way we think about the uniqueness of how humans use and understand language.
Co-first author Lilla Magyari, also from ELU, and an Associate Professor at the University of Stavanger’s Faculty of Social Sciences, said the research was important for dog owners but also had important implications for theories and models of language evolution.
“Because typical dogs learn instruction words rather than object names, and there are only a handful of dogs with a large vocabulary of object words, our research definitely showed it’s not uniquely human to have this type of referential understanding of object words. Dogs can understand more than they show signs of knowing. They don’t merely learn a specific behaviour to certain words, they might actually understand the meaning of some individual words as humans do,” she said.
The researchers are now curious to discover if this ability to understand referential language is specific to dogs or could be present in other mammals as well. They hope future research will examine how this ability emerged and if it is dependent on dogs’ unique experience of living with people.
Anne Layton-Bennett