Dogs Can Tell When You’re Smiling

Mar 04, 2015, by Dr. Becky Coats

Dogs and SmilesIn research findings that will come as little surprise to pet owners, researchers have confirmed that dogs can tell the difference between a smile and an angry expression, even in unfamiliar faces. This is the first evidence that animals can actually identify human expressions. But researchers warn they haven’t confirmed that dogs understand the expressions.

Putting Dogs to the Test

To determine whether dogs could tell the difference between happy and angry expressions, dogs were shown 15 picture pairs of happy and angry expressions–but were shown only half the face (either the top half or the bottom half) in each case. Some dogs were rewarded for learning to identify the happy face. Others were rewarded for learning to identify the angry face.

Then the dogs were put to the test using four different experiments. They were asked to select the angry or happy face in four different contexts:

  • New faces showing the same half of the face as training
  • The other half of faces used in training
  • The other half of new faces
  • Only the left side of faces used in training

Researchers found that dogs did better than chance in all four tests. They postulate that dogs couldn’t have done that if they hadn’t been able not only to learn the clues from facial expressions, but also to extrapolate from one set of clues (eyes, for example) to another set of clues (the mouth).

However, they note that the research doesn’t prove that dogs actually know what the expressions mean. On the other hand, many animal experts and pet owners are convinced that dogs actually do know what our emotions mean.

Smiles Were Easier to Learn

Another interesting outcome of the study was that researchers found it was easier to teach dogs to pick out the smile for a reward than to teach them to pick the angry face. Researchers suggested this was because dogs might have entered the research with a preconceived notion that it was best to avoid people with an angry face and that they certainly couldn’t expect a reward for touching an angry face with their nose.

But it’s also possible that dogs have something similar to what humans have when we look at faces. People recognize smiling faces faster than any other expression and can identify them from farther away than other expressions. It seems our brains are truly designed to pick up on smiles, which is why it’s good to share them.

If you don’t have a smile that you feel comfortable sharing with anyone but your dog, cosmetic dentistry may be able to help. To learn how we can give you a share-worthy smile, please call (817) 481-6888 for an appointment with a Grapevine cosmetic dentist at Grapevine Dental Care.