Dogs Can Read Your Facial Expressions

Dog lovers would be the first to agree that these faithful companions know when their human friends are happy or sad. Those who have a dog in their lives are completely convinced that their beloved pets are in tune with their moods and ready to comfort at any time. Scientific research however has never been able to prove this level of knowledge by dogs. That could be changing with a study done in Austria and released this month in the Cell Press journal Current Biology. Biologist Corsin Müller of the University of Veterinary Medicine in Vienna, Austria, and colleagues tested 20 dogs—including breeds like border collies, a fox terrier, a golden retriever, a German shepherd, and even some mutts—using a touchscreen. The scientists trained the dogs to touch either a happy face or an angry face, using treats of course. The dogs were rewarded based on which face on the screen they touched. While just about half the dogs learned to touch a happy face and half the dogs were rewarded when touching an angry face, it took three times longer to teach a dog to touch an angry face according to researchers. Prof. Ludwig Huber, the lead researcher in the study said, "It seems as if they don't like to touch an angry face." Prof. Huber also explained that the goal of the study “is the big question of communication. How is it that dogs are so adapted to humans, and what's happened during the process of domestication?" Of the original 20 dogs used in the study, 11 of them learned the task well enough to move on and continue being tested. For instance, researchers required the dogs to look at different faces than they had originally seen. In another test the dogs were shown different parts of the same human faces they had seen before. Showing dogs the opposite half of the face they had learned to recognize in their training, showed they could "transfer their knowledge" of human facial expressions. Müller explained that both the top half and the bottom half of the faces were used to ensure the animals weren't just responding to a smile or the baring of teeth. Müller was quick to point out that emotions show on all parts of a human face, not just the mouth. "If you're angry, a wrinkle between the eyes shows up," he explains. Researchers cannot say for sure where the dogs' ability to discriminate between the two expressions comes from. It could be from the domestication process or from the past experiences of the dogs. Despite it’s origin, Müller was not surprised that the dogs were able to tell certain facial expressions apart. "Because they spend so much time with humans, they have a lot of opportunities to see human expressions," he said. Müller has plans to further study where the ability may have developed and for that he will need to expand the research to other species such as cats, pigs and hand-raised wolves. While this study is the first to document the actual ability of dogs to recognize human emotions from facial expressions, dog owners have believed all along that their pets know when they are happy or sad. Perhaps the ability to read faces is just one of the many reasons dogs are considered man’s best friend?