Animal Intelligence: Dogs Understand and React to Human Emotions

Can your dog tell what you're thinking? Maybe not, but a new scientific study suggests they can at least register your emotions by looking at your facial expressions.

In an experiment, scientists showed dogs images of people expressing anger, fear, happiness, sadness, surprise, disgust or being neutral, according to a press release. The dogs' heartbeats would increase when they saw photos of angry, fearful or happy people, and they took longer to start eating again after seeing them. The researchers believe this means that the dogs were more stressed after seeing "arousing" emotions from humans.

Dressed Up Dog
A dog wears a tiara and sunglasses ahead of Britain's Queen Elizabeth and Meghan, the Duchess of Sussex, visit to Chester. REUTERS/Jon Super

They also consistently turned their heads to the left when they saw images of angry, fearful or happy people. When faced with a surprised human expression, the dogs turned their heads to the right. The scientists suggest this indicates dogs may use different sides of their brain to process different information.

"Clearly arousing, negative emotions seem to be processed by the right hemisphere of a dog's brain, and more positive emotions by the left side," Marcello Siniscalchi from the Department of Veterinary Medicine at University of Bari Aldo Moro in Italy said in a press release.

The scientists published their results in the journal Springer Learning & Behavior. While this research only involved a small sample size of 26 dogs, the results support a former study demonstrating that dogs can see, hear and smell different emotions on humans. The same scientists who led the new research on dogs understanding human expression also found that dogs are sensitive to emotional human vocalizations.

Research continually shows us that nonhuman animals can understand a lot about humans. For example, sheep can recognize human faces, dolphins anticipate play with people, and cattle prefer to stand closer to humans who have been gentle with them. Man's best friend has been by our side for thousands of years, so it only makes sense that they would come to understand and interpret our feelings in one way or another.