Holistic processing of conscious and unconscious faces

Previous research suggests that holistic face processing is implicated in face recognition. However, little is known about the role of consciousness in holistic face processing. The present study explores the holistic processing of conscious and unconscious faces. Holistic processing was measured by the composite task, in which composite faces were created by combining top and bottom regions of two different faces, and participants were asked to judge if the top halves of two consecutive composite faces were the same or not. Holistic face processing is typically observed in the composite task through interference on judgments of the target (top) halves from variations in the irrelevant (bottom) halves of faces. In addition, continuous flash suppression (CFS) was utilized to present some stimulus components unconsciously. In Experiment 1 (E1), participants performed the composite face task with the irrelevant bottom halves of faces presented consciously (monocular) or unconsciously (CFS). Results showed that the composite effect was only found in the conscious condition, but not in the unconscious condition. To test whether the bottom halves of faces could be processed at all in the unconscious condition, the following experiment embedded catch trials in the composite tasks. In the catch trials, the bottom half (irrelevant) of the presented composite, along with the bottom half of a novel composite were presented and participants were asked to choose the one they saw. As in E1, the composite effect was only observed when irrelevant components were consciously perceived. However, identification performance of bottom halves on the catch trials was above chance, showing that participants did have access to some information about them, but this information did not affect judgments of the target (top) halves of faces in the composite task. Taken as a whole, these results show that unconscious face information does not appear to be processed holistically.