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 congruency 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, 2013). To further probe the influence of perceptual grouping cues on holistic face perception, participants made part-matching judgments about faces presented in either an intact external (oval) frame or a frame made from misaligned oval parts to discourage the grouping of the face halves into cohesive (object) unit. Notably, the external contour of the face image in the misaligned frame condition is the same as that in the standard misaligned condition used in the composite task indexing holistic perception. However, unlike in the standard misaligned condition, the configuration of features within the face remained intact. For comparison, participants also made part judgments about faces where both the face parts and frames were misaligned together (i.e., as in the standard misaligned condition). Intriguingly, the effect of disrupting only the frame, and not the configuration of the face, on the congruency effect was indistinguishable from that of disrupting both the frame and configuration together. This comparable attenuation of holistic perception by the disruption of basic perceptual grouping mechanisms provides further support for the contribution of such mechanisms to holistic face perception.
Curby, K., & Entenman, R. (2015). Framing of faces: similarly impaired holistic perception from disruption of grouping- and configural- cues. Journal of Vision, 15(12), 152. https://doi.org/10.1167/15.12.152