We’ve all heard of racial profiling, but what about facial profiling? It may sound silly, but new research from a team of Brock University psychologists suggests that we subconsciously ascertain possible aggression in others based on their facial structure. The findings, published recently in Psychological Science, show that face shape — specifically a measurement called facial width-to-height ratio (WHR) — may influence the instant judgments we make about others. Not only that, but the Brock University study demonstrates that these automatic predictions can be remarkably accurate. 

Volunteers participating in the experiment were briefly shown photographs of the faces of men with a history of aggressive behavior, and asked to rate how aggressive they thought each person was based simply on what they saw. Even after viewing a photo for a mere 39 milliseconds, volunteers’ estimates tended to correspond closely to the actual aggressive behavior of the men in the pictures. Researchers also found that the participants judged men with larger facial width-to-height ratios as more aggressive.

WHR is a measurement of the distance between the right and left cheeks and the distance from the upper lip to the mid-brow. In the Brock University study, men with greater WHR received a higher aggressiveness rating by volunteers. 

History has shown that physiognomy is an imperfect science, so while it may seem that this study indicates a reliable link between facial structure and personality, it probably reveals more about the visual cues we use to predict personality traits in one another.