Why a wide-eyed expression of fear can be a good thing

Wide-eyed expressions that typically signal fear seem to enlarge our visual field making it easier to spot threats at the same time they enhance the ability of others to locate the source of danger, according to new research from the University of Toronto.

The research by Daniel Lee, a graduate student in the Department of Psychology, is published on the Psychological Science website and in an upcoming issue.

“Emotional expressions look the way they do for a reason,” says Lee. “They are socially useful for communicating emotional states, but they are also useful as raw physical signals. In the case of widened eyes, they help send a clearer gaze signal that tells observers to ‘look there.’”

Lee, his supervisor Adam Anderson, also of U of T’s psychology department, and Joshua Susskind of University of California, San Diego first found that participants who made wide-eyed fear expressions could literally see more: they were able to discriminate visual patterns farther out in their peripheral vision than participants who made neutral expressions or expressions of disgust.

Next, they investigated the benefits that wide-eyed expressions might confer to onlookers. They found that participants were better able to tell which direction a pair of eyes was looking as the eyes became wider. And these wider eyes helped participants respond to targets that were located in the direction of the gaze. Importantly, these benefits did not depend on recognizing the eyes as fearful.

Wide-eyed expressions are helpful for onlookers quite simply because as eyes become wider, we can see more of the iris and whites of the eyes, known as sclera, Lee says. This directly increases the physical contrast and information signal, making it easier to tell where someone is looking.

“Our eyes are important social signals,” says Lee. “This research really shows how social we are wired to be.”