Abstract:

It is well known that same-race faces are better discriminated and recognized than other-race faces, a phenomenon confirmed experimentally and termed in the literature for face perception as the “own-race advantage”. Why do people have the bias in face processing? Some researchers claimed that the own-race advantage in discrimination is associated with interracial contact. The more visual experience with own race faces, the better discrimination within own-race faces. How visual experience affects the processing of same-race and other-race faces has yet to be determined. An influential hypothesis “experience-based holistic processing view” states that it would result from a reduced holistic processing with which we have less experience. To examine the effect of perceptual experience on holistic processing, with composite face paradigm and perceptual adaptation paradigm we investigated the composite-face effect of own-race faces, other-race faces and morphed faces during the perceptual discrimination. In the preliminary experiment, 20 Asian participants were presented with 704 color Asian-Caucasian morphed face stimuli for a race categorization task. These stimuli were generated with morphing software (MorphTM), allowing the creation of 11 blended face stimuli (from 0:100 to 100:0 for Asian:Caucasian proportions, respectively) for each of 64 Asian-Caucasian continua. In each continuum, the face that was equally often categorized as Asian and as Caucasian was identified as the ambiguous-race face. Result showed that the 52 Asian-Caucasian ambiguous faces were extracted and used as face stimuli in experiment 1a, experiment 1b and experiment 2. In Experiment 1a, we examined the holistic processing of own-race faces and other-race faces by using the composite paradigm in a two-alternative forced-choice delayed matching task. The results of Exp1a showed that own-race faces and other-race faces are processed holistically. However, morphed faces are not processed holistically. With gray pictures as stimuli, Exp1b replicated the same results as experiment 1a. In Experiment 2, we examined that the holistic processing of morphed faces can be induced by perceptual adaptation (5 seconds). Results showed that the morphed faces were processed holistically after short-term perceptual adaptation. Collectively, these findings indicate that face holistic processing is modulated by perceptual experience, even the short-term perceptual adaptation may affect participants’ face holistic processing as one of the most important factors.

Key words: perceptual experience, holistic processing, composite-face effect