Making Snap Judgments about a Stranger's Personality

Faculty Mentor(s)

Dr. Thomas Ludwig, Hope College

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How do people decide whether a stranger might be able to help them, or even whether it is safe to approach that person? Previous research has demonstrated that a brief glimpse of a face is enough for you to make a judgment about the trustworthiness, competence, and potential threat of a stranger. This study explored the role that the left and right brain hemispheres play in judging personality traits of individuals whose faces are presented very briefly on a computer screen. Participants rated the competence and aggressiveness of 100 faces, each presented for only one-tenth of a second. The faces had been carefully constructed so that the left and right halves of the face could display different levels of the emotional expressions related to dominance and threat. Of the 100 faces, 25 were HH (high level of dominance/threat on both sides), 25 were LL (low on both sides), 25 were HL (left half was high, right half was low) and 25 were LH (left half was low, right half was high). Current theories of face perception suggest that the features displayed in the left visual field of the viewer (projected to the right hemisphere of the viewer’s brain) should have greater impact on the viewer’s rating of each face, due to the right hemisphere’s general dominance in processing emotion signals.

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