Neural Correlates of Implicit Processing of Other-Race Faces.

Abstract describing the poster (50 words): The aim of this study was to investigate the neural correlates and the time course of implicit processing of 'other race' faces. We utilized a masked priming paradigm. Half prime-target pairs were Asians and half Caucasians. The evented-related potential results indicated an early and automatic other race effect. Supporting summary (500 words): Although it is well established that people are better at recognizing faces from their own-race than at recognizing faces from other races, an effect known as the Other-Race Effect (ORE), relatively little is known about the neural correlates underlying their on-line processing. The aim of the present study was to investigate the neural correlates and the time course of implicit processing of "other race" faces. To this end, we utilized a masked priming paradigm, using a prime duration of 33 ms, while recording the event-related potentials (ERPs). Two types of prime-target pairs were used: 1. Congruent (prime and target were identical faces); 2. Incongruent (prime and target were different faces). Half prime-target pairs were Asian faces and half Caucasian faces. The faces on each prime-target pair belonged to the same race and gender. The prime was 25% smaller than the target to avoid any perceptual overlapping. Each trial began with a fixation cross (+) in the middle of the screen. Five hundred milliseconds later, a 500 ms black screen that was replaced by a 500 ms forward mask, was presented. The forward mask was replaced at the same location on the screen by the prime stimulus for 33 ms. The prime was then immediately replaced by a 500 ms backward mask. Then appeared the target stimulus, which remained onscreen until a response was made. Each response was followed by a 1000 ms blank screen. The forward and background mask stimuli were scrambled faces with the same luminance and contrast of the prime and target. The task of the participants (all Caucasians) was to indicate, as quickly and accurately as possible, whether the target face was female or male. The behavioral results showed an ORE effect, with slower reaction times (RTs) for Asian than Caucasian faces, and a congruency/priming effect, with faster RTs for the congruent than congruent condition. There was no interaction between race and congruency. The ERP results indicated an automatic/implicit other race effect across all ERP components analyzed (P1, N170, N250, P3) and a congruency/priming effect on late components (N250, P3). The congruency/priming effect was larger for Asian than Caucasian faces, showing a greater difficulty to process faces belonging to another race. These results suggest that race identity can be processed early and unconsciously in the brain to some degree of abstraction.