Dogs visualize their owners face.

This is a pretty darn cool study :)

To investigate, the researchers recruited 28 pooches and their owners. In each experimental session, the dog's owner or another familiar person positioned the dog about a meter away from a computer monitor hidden behind a screen. Then, the researchers played a recording of either the owner or a stranger saying the dog's name five times through speakers in the monitor. Finally, the researchers removed the screen to reveal a still image of either the owner's face or the face of a stranger. Video cameras recorded the dogs' reactions.

When the owner's voice preceded the owner's face, dogs looked at the screen for about 6 seconds on average. The same was true when the researchers paired a strange voice with a strange face. But when a stranger's face followed the owner's voice (or vice versa), the dogs spent an extra second or two staring at the monitor, suggesting that they realized something was amiss, Adachi says. (Similar methods have been used to test face recognition in human infants (ScienceNOW, 17 May 2002). Adachi suspects that the sound of an owner's voice conjures up a mental image of the owner's face--and leads to confusion when another face appears instead. He and his colleagues report their findings in the January issue of Animal Cognition.

I really get a kick out of very 'simple' studies.