Newsflash: Dogs Understand Mean Words Said In a Friendly Tone
Most of us have noticed that we can say pretty much anything to our dogs in an affectionate, high-pitched tone of voice, and they'll wag and look happy. This may lead us to believe that they have no idea what we're saying. But a recent study from Hungary published in Science Magazine suggests that dogs may be able to understand quite a bit more about language than we think.
Dogs, like humans, process words on the left side of the brain and vocal tone on the right side of the brain. They also have reward centers of the brain, which activate in response to pleasurable experiences like treats, cuddles, and words of praise from their trainers. The thirteen dogs in the study were first trained to sit very still in the fMRI scanner. Researchers then played recordings of the dogs' trainer saying positive and neutral phrases in either positive or neutral tones of voice.
The researchers expected the dogs' reward centers would light up in response to both positive and neutral phrases when those phrases were spoken with a positive tone. This would support the idea that dogs don't actually distinguish the content of words from the tone of voice in which they're spoken - i.e., you can say whatever you want to your dog, and as long as you sound happy when you do it, she'll wag.
But the results showed otherwise. The dogs responded far more to the combination of positive words with positive intonation than to neutral words with positive intonation. Happy words meant just as much as a happy tone of voice.
This suggests a number of interesting things. For one, it means that dogs are at least somewhat able to distinguish between tone and content of spoken words, which is a lot more sophistication than we often give them credit for. For another, it suggests that we humans (as far as our brains are similar to those of dogs, which is a lot more than some of us would like to believe) may have evolved the brain mechanisms needed to process language long before we began to invent language itself.
This is a small study - one trainer voice, thirteen dogs - but the results are certainly intriguing, and worth thinking about next time you tell your dog "Stock market radiator spatula bucket!" in a sweet and encouraging tone of voice. (Wait, you don't do that? Okay, just me then.)