No one's really sure why dogs tilt their heads - except when it's used to exploit our emotions straight after they’ve pooped on the carpet. According to a survey by Psychology Today, it might be to do with vision.

Dogs are extremely emotionally intelligent. They have an acute ability to understand our body language and pick up on our vocal cues – even subtle inflections or specific words they associate with fun activities. As part of their body-language-reading arsenal, they also constantly “read” our faces for information on our emotional state.

According to Stanley Coren, who conducted the survey, dogs tilt their heads so they can see our facial features better, as their muzzle blocks out the lower half of our faces. Along with our eyes, the mouth is an important component of human emotional expression, especially for dogs who pick up on whether our teeth are exposed or not. If you put your fist in front of your nose, you can get a picture of what it’s like with muzzle-vision (maybe don't try this in front of office colleagues).

Coren’s survey asked 582 people to complete an online survey about their dogs. Of the respondents, 62% said their dog regularly tilted its head when spoken to.

Crucially, only 52% of the owners of flatter-faced dogs (such as pugs and bulldogs) said their dog tilted its head. On the other hand, 71% of the owners of dogs with larger muzzles (such as greyhounds) reported that their dogs often tilt their heads when spoken to. The statistical gap between long-muzzled and short-muzzled dogs led Coren to conclude that head tilting was at least in part due to their muzzle's impact on vision.

However, more than half of flat-faced dogs is still a pretty high proportion. Coren suggested this is probably due to the positive response dogs get when they tilt their heads.

"Perhaps something to do with hearing plays a role, or perhaps the dogs are really just trying to look cute. Nonetheless, this study is a first step toward finding the answer, and at least we now have a bit of data to work with," Coren said in his article. Or maybe the simplest answer is the best: perhaps it's just a sign of confusion.

[H/T: Psychology Today]