By tilting its head slightly to the side, a dog can melt the heart of even the most hardened cat person. Most everyone finds this behavior adorable, but few people can explain what compels a dog to do it. Are dogs somehow aware of the effect they have on humans, using a cute trick to exploit us for affection?

Experts say the real answer lies with your dog's ability to process information. According to a study published in the journal Animal Cognition in October 2021, dogs tilt their heads when they recognize words that are significant to them. A team of scientists from the Family Dog Project research center observed 40 dogs for the study. Over the course of three months, the pets' owners taught them the names of different toys.

Most of the dogs didn't know the difference between the words by the end of the trial, but those that did know the difference exhibited an interesting behavior. When these so-called "gifted" dogs heard the name of a particular toy, they tilted their heads to one side as if to listen more closely. As the researchers write in the study, this suggests that the pets recognized the names as important words that warranted all of their attention.

These findings align with previous theories on head-tilting in dogs. Dogs are impressively good at reading and responding to our body language and vocal cues. When you're lecturing your pooch for taking food off the counter, they're taking it all in even if the literal message gets lost in translation. Same goes for when you’re giving your pup praise. Dogs are capable of recognizing certain parts of human language, so when they cock their heads as you speak to them, it's possible they're listening for specific words and inflections they associate with fun activities like meals and playtime.

The head-tilt may also have something to do with how the canine ear is constructed. Even though dogs sense frequencies humans are incapable of hearing, their ability to detect the source of sounds is less precise than ours. A dog's brain calculates extremely minuscule differences between the time it takes a sound to reach each ear, so a simple change in head position could provide them with useful sensory information. When dogs tilt their heads, some experts believe they are adjusting their pinnae, or outer ears, in order to better pinpoint the location of a noise.

Stanley Coren of Psychology Today believes that vision also has something to do with this behavior. If you try holding your fist in front of your nose, you can get a fair sense of what it’s like to view the world with a muzzle. When watching someone speak, the "muzzle" will block the lower part of their face from view, and if you tilt your head to one side you will be able to see it more clearly. In addition to being able to perceive emotional cues in our voices, dog can also read our facial expressions. When cocking their heads to the side, Coren suggests that dogs are trying to get a better view of our mouths, where our most expressive facial cues originate.

The 2021 study in Animal Cognition complicates these theories, however. The dogs that cocked their head in response to the names of their favorite toys were more likely to tilt it to a specific side, no matter what direction the command was coming from. So while head-tilting may help dogs look or listen better in some cases, these physiological factors don't explain every instance. As for why some dogs tend to lean their heads to the same side, the researchers don't know for sure. We do know that dogs can be left- or right-pawed in the same way humans are left- or right-handed, and this side preference may extend to the head.

If your dog is a frequent head-tilter, this could mean that they're especially empathetic. Some experts have reported that dogs who are more socially apprehensive are less likely to tilt their heads when spoken to. But if your dog doesn't display this behavior, there's no need to automatically label them as a canine sociopath (especially if they have pointy ears or a flatter snout). And even if the head tilt does come from instinct, the more owners respond to it with positive reinforcement, the more likely dogs are to do it in search of praise.

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