Abstract
The mechanisms that integrate facial features into holistic perceptual units are relatively unknown. Evidence suggests that basic perceptual grouping mechanisms can contribute to holistic face perception: holistic processing of face, but not non-face objects, indexed via the composite effect, is significantly reduced when the backgrounds upon which faces are presented are themselves misaligned and colored differently, cues that discourage grouping of face halves into cohesive (object) units (Curby, Goldstein, & Blacker, in press). Notably, grouping of elements into objects is flexible and shaped by experience (Zemel et al., 2002). Thus, if attenuation of holistic face perception by shape and color cues that discourage grouping reflects an impact on the perceived "objecthood" of the face, it should be possible to shape this effect by manipulating observers’ experience with these cues. Here we tested this hypothesis using a pre-task, in which participants searched for a target among arrays of dual-colored, misaligned conjoined rectangle pairs (forming irregular octagons) (group-1) or single rectangles (group-2). This pre-exposure to the background shapes was designed to encourage their perception as either a single, dual-colored irregular octagon (facilitating grouping of face parts that later appeared on them) or as two independent rectangles (facilitating the independent perception of face parts appearing on them). Results revealed that holistic face perception was significantly modulated by experience with the background shapes: When appearing on the different colored, misaligned rectangle backgrounds, face parts were perceived more holistically by those who had completed the pre-task encouraging perception of the background as a single octagon, relative to those who had completed the pre-task reinforcing the perception of the background components as independent rectangles. This modulation of holistic perception by grouping cues is surprising given the often assumed impenetrability of holistic face perception, and it provides potential insights into the elusive mechanisms underlying holistic face perception.
Meeting abstract presented at VSS 2013