| dc.description.abstract | While traditional face perception predominantly focuses on perception of individual
faces viewed alone, we frequently interact with faces in groups. This thesis examines
contextual effects on person perception, specifically how the presence of other people
influences judgments of an individual face either viewed directly (foveally) or not
(peripherally). We first examined this by measuring a target face’s perceived direction
of gaze as a function of its emotional expression and presentation eccentricity. The face
was viewed centrally or peripherally and was surrounded by flanking faces whose gaze
deviation and emotional expression also varied. We find that when the target face was
viewed peripherally, participants judged its direction of gaze to be direct over a wider
range of gaze deviations than when viewed foveally, and more so for angry faces than
neutral faces. However, its perceived direction of gaze was not influenced by the
presence of flankers. Next, we measured contextual effects of age perception for faces
viewed centrally, by measuring the perceived age of a target face in the presence of
differently aged faces surrounding it (younger or older than target face). We find that
when a target face is surrounded by younger faces, it systematically younger older than
when viewed on its own, and when it is surrounded by older flankers, it systematically
appears older than when viewed on its own. This result holds irrespective of gender or
race of the stimuli or the observers. In a final experiment, we tested how personal
familiarity with faces as well as their emotional expressions influences mean emotional
ensemble perception to investigate how different faces contribute to the overall mean
judgement, and whether it is modulated by the relationship between the observer and
individuals in the group. We find that when all faces in the ensemble are unfamiliar, a
high intensity emotional expression face biases ensemble mean perception towards its
expression. However, when a familiar face was present, the perception was biased towards its expression regardless of its intensity. Overall, those findings suggest that face
perception is strongly shaped by the spatial context in which faces are presented. | en_US |
