People seem to have a general consensus on dogs’ facial expressions, but empathetic people feel those expressions a little more strongly.

A study conducted by researchers at the University of Helsinki and Aalto University aimed to characterize how human observers detect and rate affect in dog facial expressions in comparison with human expressions and to look at the effect of psychological factors on their ratings. These psychological factors included the observers’ levels of empathy, their dominant personality traits, and their previous experience with dog behavior. The study was published in PLOS One in January 2017.

Researchers asked 34 observers—15 men and 19 women—to rate images of human and dog faces with pleasant, neutral, and threatening expressions. Each observer looked at 30 human and 30 dog actors, with 10 in each emotional category—threatening, neutral, and pleasant. As a control, they were also presented 10 general household objects and 10 abstract images. For each image, the observer had to answer eight different questions evaluating how positive and negative they found the images and the emotional content of the image, e.g. How much happiness does the image contain?

After rating the images, subjects completed questionnaires sampling their personality, their human-directed empathy, and their animal-directed empathy.

In general, human faces were rated more positive than dog faces, except with neutral expressions, where dog faces were rated more positive. Pleasant dog faces were rated more positively, but were not rated at positively as pleasant human faces. In the same vein, threatening dogs were viewed more negatively than threatening humans.

Emotional empathy had the clearest influence on these ratings. Subjects with higher empathy also made judgments more quickly. Subjects with higher emotional empathy evaluated threatening faces of both species as more negative and higher in anger. They also rated the happiness of pleasant humans higher.

The participants with more experience or exposure to dogs estimated neutral dogs as more positive and were more reactive to pleasant dogs, but it did not affect their judging the aggressiveness of threatening dogs. This finding along with previous studies suggests experience with dogs is not necessary to interpret basic facial expressions of dogs.

Photo credit: © iStock/Kosamtu