Social Judgments of Faces along Different Dimensions
Authors:Poonim Daya, Shuo Wang
Mentor:Ralph Adolphs, Professor of Psychology and Neuroscience, California Institute of Technology
In everyday life, people constantly form judgments of others based on purely facial features. The chief objective of this study is to determine how the brain picks up subtle changes in facial structures by investigating perception along different facial dimensions. Established software was used to create sets of faces that vary along one dimension to another: “happy vs. fearful”, “anger vs. disgust”, “anger vs. fearful”, “male vs. female” and more complex social dimensions, like dominance and trustworthiness. We presented subjects with faces and asked them to judge the face as well as rate their confidence while recording their choices, reaction times, confidence levels, and eye fixations. Subjects were able to pick up subtle changes in facial structures regarding emotion and gender, based on the relationship between the strength of an emotion and the percentage of times that emotion was chosen. We found a significant difference between patients with bilateral amygdala lesions and healthy controls in judging trustworthiness, while we did not observe any significant difference between controls and people with autism. Continuation of this study could involve investigating the brain structures involved in facial judgments using fMRI.