Humans love it when dogs cock their head to one side, but no one really knows why, and there have been few studies into the adorable phenomenon. Some have speculated dogs tilt their head to better hear certain frequencies or see past their snouts. But results of a new experiment suggest it's "linked to mental processing—a sign of high attentiveness or concentration in the gifted dogs."
From Science:
The researchers stumbled upon their find by chance while conducting a study of "gifted word learner" dogs. Most dogs can't memorize the names of even two toys, but these talented pups—all border collies—could recall and retrieve at least 10 toys they had been taught the names of. One overachiever named Whisky correctly retrieved 54 out of 59 toys he had learned to identify.
Over the course of several months, the researchers tested the dogs' abilities to learn and recall labels for toys, comparing their skills with those of 33 "typical" dogs. Owners placed toys in another room and asked for them by name. Only the seven gifted dogs were able to rapidly learn and remember names. But these dogs shared something else in common: the head tilt.