By Mark DaCosta- My landlord’s dog is about a year old, and he has chosen me. I work from home, so I am a constant presence in his world, and he has repaid my company in the currency he probably knows best: gifts. He slips out, visits the neighbours’ doors, and returns with their slippers and shoes, laying them at my feet with unmistakable pride.
I have lived with animals my whole life. Two dogs and two cats share my home now. I know the ordinary repertoire of a dog’s affection, and this is something else. When I speak to him, he looks at me as though he is working out what I mean. So, I did some research because his behavior is most interesting.
It turns out that scientists have begun to take that look seriously.
More than tone of voice
For a long time, the sceptical view held that dogs only read us. Say “walkies” in a bright voice while reaching for the leash, and any dog will respond. Tone and body language, the argument went, explain everything.
In 2016, Attila Andics and his colleagues at Eötvös Loránd University in Budapest put that view to the test. They trained dogs to lie still in a brain scanner, awake and unrestrained, while their trainers spoke to them. The dogs processed the meaning of words mainly in the left hemisphere and the emotional tone of the voice mainly in the right, which is the same division of labour found in human brains. The brain’s reward regions responded most strongly only when praise words arrived in a praising tone. Warm words in a flat voice, or a cheerful voice wrapped around meaningless words, did not light them up in the same way (Andics et al., Science, 2016).
In other words, the dogs were listening to what was said and how it was said, and combining the two.
A word that calls up a picture
A second question is whether a word means anything to a dog beyond “do this now.” In 2024, Marianna Boros and colleagues recorded the brain activity of dogs as their owners named a familiar object, such as a ball, and then showed either that object or a different one. When the object did not match the word, the dogs’ brains produced a surprise response resembling one seen in humans when a word does not fit what we expect. The finding suggests that hearing the word called up some picture of the object in the dog’s mind (Boros et al., Current Biology, 2024).
The most famous demonstration is Chaser, a border collie whose owner taught her the names of more than a thousand objects. She could fetch an item by name, and when given an unfamiliar word she would pick out the one object she had never seen named, reasoning by elimination (Pilley and Reid, Behavioural Processes, 2011). Chaser was an extraordinary animal, trained with extraordinary dedication. But she shows what a dog’s mind can do when someone takes the trouble to teach it.
Why dogs?
The likely explanation lies in a very long partnership. Over thousands of years, dogs have lived inside human households, and those that read us best were the ones that thrived. The result is an animal tuned to our voices, faces and gestures in a way few other species match. Parrots, dolphins and great apes have impressed researchers too, but dogs are the ones asleep on our sofas.
What the slippers mean
So what does my landlord’s puppy understand? Probably a modest handful of words, learned through repetition and reward: his name, “good boy,” perhaps “shoes.” The slippers are the part I cannot explain. He may know the word. He may only have learned that footwear earns a delighted reaction. Most likely it is a mixture, and he is reading my face and my tone as much as my vocabulary. For an animal not yet two years old, that is no small accomplishment.
The temptation is to go to one extreme or the other: to treat dogs as small people in fur coats, or to wave away everything they do as conditioning. The evidence supports neither. Dogs have limits, but their brains handle our speech in ways that are surprisingly familiar, and some of them are plainly trying to understand us.
That is what moves me about this one. Nobody asked him to learn my language. He is learning it anyway, one slipper at a time.
