Published in the journal Biology Letters*the study aimed to determine whether dogs could recognize emotions expressed by humans and their peers by combining multiple sources of sensory information. The researchers wanted to know if this ability was a simple learning process or a real cognitive processing of emotions.
To check this, the researchers tested 17 adult pet dogs. The animals were placed in front of 2 images displayed simultaneously. One showed a positive expression (happy human face or doggie in play posture); the other a negative expression (angry face or aggressive peer). At the same time, a sound was broadcast, that of a human voice or a canine vocalization with a positive or negative tone.
The scientists then observed which image the canines looked at the longest. If they correctly matched the sound to the corresponding facial expression, it demonstrated that they were able to identify and categorize perceived emotions.
Dogs are able to physiologically distinguish our emotional states
According to the results, the dogs spent more time looking at the face whose emotional expression matched the sound they heard. This behavior has been observed with both human faces and those of other doggies.
According to the authors of this study, this performance shows that our 4-legged companions are capable of integrating visual and auditory information to recognize an emotional state. They do not just react to a smile, a grimace or a particular intonation taken in isolation. They construct a coherent mental representation of the emotion expressed.
This ability also suggests that positive and negative emotions are not processed in the same way by their brains. A happy face does not elicit the same cognitive response as an angry or threatening face, evidence that dogs truly make a physiological distinction between these emotional states.
Our 4-legged companions are very attentive to our emotions!
This discovery reinforces the idea that the relationship between humans and dogs is based on a particularly developed emotional understanding. After thousands of years of cohabitation, doggies seem to have acquired a remarkable ability to decipher our states of mind.
For owners, it also reminds us that our companions are sensitive to much more than our words. The tone of our voice, our facial expressions and our general attitude provide them with valuable information about our mood. Our faithful companions can thus perceive whether we are relaxed, happy or, on the contrary, tense and upset.
* “Dogs recognize dog and human emotions”, Natalia Albuquerque, Kun Guo, Anna Wilkinson, Carine Savalli, Emma Otta, Daniel Mills, Biology Letters, January 2016.