First impressions: Do faces with scars and palsies influence warmth, competence and humanization?

A glance is enough to assign psychological attributes to others. Attractiveness is associated with positive attributes ('beauty-is-good' stereotype). Here, we raise the question of a similar but negative bias. Are people with facial anomalies associated with negative personal characteristics? We hypothesized that biases against faces with anomalies arise because of negative stereotypes (less warmth and competence) and forms of dehumanization (animalistic and mechanistic). We enrolled 1493 mTurk participants (N = 1306 after exclusion) to assess 31 traits of photographed people using 60 pairs of photographs of the same person before and after plastic surgery. Half anomalous faces had a scar and the other half had a palsy. To calculate warmth and competence, we conducted a principal components analysis of the 31 attributes. Animalistic dehumanization was assessed by averaging reverse-scored ratings corresponding to moral sensibility and rationality/logic, and mechanistic dehumanization by averaging across reverse-scored ratings corresponding to emotional responsiveness and interpersonal warmth. We found that both kinds of anomalous faces were seen as less warm, competent and were dehumanized. Our findings suggest that an 'anomalous-is-bad' stereotype generalizes regardless of the aetiology of the anomaly. This effect may be related to a reverse halo effect, that is, the horn effect.