Yet another study reports that dogs are capable of processing a person's negative and positive emotions based on facial expressions.
It's something we've all been wondering for a long time, and it appears that our assumptions were correct – dogs can in fact read our emotion relatively well. But beyond that, dogs also react to these emotions accordingly because their brain can process if it's a negative or positive emotion based on a man's facial expressions.
“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.”
For instance, when a dog sees a man looking angry, fearful or happy, it would turn its head to the left. The dog's heart rate would also rise to indicate that it is aware someone is expressing a highly charged emotion. When a dog sees a sad or surprised look on a man's face, it would turn its head to the right.
Experts Marcello Siniscalchi, Angelo Quaranta and Serenella d’Ingeo from Italy’s University of Bari Aldo Moro published their findings in the journal Learning & Behavior. Their research is the newest proof that highlights just how much dogs are connected to humans.
Reading Emotionally Charged Expressions
While feeding 26 dogs, the research team showed the animals different photos of male and female adult faces. The images depicted a wide range of emotions: happiness, anger, fear, sadness, surprised and relaxed. The photos were carefully placed by the dog's line of sight and next to their feeding bowls.
When flashed with the images of humans that showed anger, fear or happiness, the researchers noted an increase in the dogs' cardiac activity. The animals also took time to get back to what they were doing (eating) after seeing the photos. Their responses indicated that the dogs had higher stress levels drawn from those arousing and emotionally charged human expressions.
Processing In Different Parts Of Dog's Brain
The researchers also noticed that the dogs tended to look to the left after seeing anger, fear or happiness in the human's faces. On the other hand, the dogs tend to look to the right when they saw a sad, surprised or relaxed face.
These responses revealed that dogs process human emotions in different parts of their brains. They use the right hemisphere to read negative emotions, while they use the left part of their brain to understand a positive emotion.
Social Cognition Among Dogs
The findings supported a previous study published in 2015 in the journal Current Biology, which pointed out how dogs have the capability to distinguish human expressions. Another study was done in 2016 and we wrote about it here. Because of these animals' close association with humans for many centuries, dogs apparently evolved and learned to develop social cognition.
However, the experts explained that the dogs might have read happiness similarly to anger or fear because humans usually expose their teeth when they smile or laugh. In the world of dogs, showing the teeth is actually seen as aggression.
But the experts said that dogs can eventually learn to associate the expression of happiness in a positive light and not as a stressor or threat. When in constant interaction with humans, dogs would be able to recognize that laugh or smile represent good emotions.
So Much In Common With Humans
These behavioral studies in animals suggest that non-verbal communication could be important to dogs just as much as it is crucial to human relationships and social behavior. It is possible that understanding different emotional states is not limited to men and women, as other species are showing they this ability too.
Interestingly, in the world of humans, a negative emotion might also elicit reactions like stress, increased heart rate, and high blood pressure. This proves once again that beyond companionship, humans, and dogs definitely have plenty of things in common.