Study: Man's Best Friend Really Can Read Your Emotions

PHILADELPHIA (CBS) – A study has found that dogs can recognize humans' emotions by combining information from different senses.

Researchers say that dogs are not just displaying learned behaviors, but they form abstract mental representations of positive and negative emotional states.

In the study, researchers presented 17 domestic dogs with pairings of pictures and sounds conveying combinations of positive and negative emotion expressions in humans and dogs.

The sounds were played to the dogs without any prior training.

Researchers found the dogs spent a significantly longer time looking at the facial expressions, which matched the emotional state of the vocalization.

This indicates that dogs have mental representations of positive and negative emotional states of others, researchers say.

Dr. Kun Guo, from the University of Lincoln's School of Psychology says, "Previous studies have indicated that dogs can differentiate between human emotions from cues such as facial expressions, but this is not the same as emotional recognition. Our study shows that dogs have the ability to integrate two different sources of sensory information into a coherent perception of emotion in both humans and dogs. To do so requires a system of internal categorization of emotional states. This cognitive ability has until now only been evidenced in primates and the capacity to do this across species only seen in humans."

"There is an important difference between associative behavior, such as learning to respond appropriately to an angry voice, and recognizing a range of very different cues that go together to indicate emotional arousal in another. Our findings are the first to show that dogs truly recognize emotions in humans and other dogs," says co-author Professor Daniel Mills.

The findings are published in the Royal Society journal Biology Letters.