“Thaaaat’s a good doggy!”

We’ve all probably already spoken to a dog in this way, and it’s perfectly normal. A study published in the journal PLOS Biology claims that humans unconsciously modify their speech rate when they address their four-legged friends.

A Franco-Swiss research team investigated how humans and dogs communicate in an experiment involving 27 volunteers and 30 canines. The researchers analysed the brain responses of the participants when they addressed other humans or dogs across five different languages.

At the same time, they studied the vocalisations produced by the dogs to understand how they communicate with their fellow dogs, as well as with other species.

It turns out that humans speak much faster than dogs do. People speak at an average of four syllables per second, while our four-legged friends emit two vocalisations per second.

However, the experts noticed that when a human speaks to a dog, they talk at a rate of three syllables per second. In other words, humans slow down their speech rate to come closer to that of the canines.

Dogs seem to be very receptive to this change of pace: their brains react strongly to delta waves, the slow, high-amplitude waves humans emit when they’re fast asleep. “Humans who speak to their dogs adopt a speech rate that differs from adult-directed speech and more closely aligns with the dog’s neural delta oscillatory capacity,” the researchers write in their paper.

So, to make yourself understood by dogs, it’s probably best to speak slowly. That said, it’s not a question of just saying everything and anything in a slow voice: research suggests that dogs pay attention not only to the musicality of what we say, but also to its meaning.

In a study published in the journal Current Biology, scientists in Hungary claim that dogs know that certain words refer to specific objects. This ability is common to all dogs, not just a few rare “superdogs” like Rico, a German border collie capable of recognising 250 toys when his name is spoken.