Abstract:

The other-race effect (ORE) refers to the own-race discrimination advantage and the other-race categorization advantage. The perceptual expertise theory explains the ORE as a result of people’s long-term perceptual exposure to own-race faces much more than the other-race faces. However, recent findings suggest that short- term, social-cognitive factors, such as reduced motivation to individuate other-race faces, may also contribute to the ORE. To examine the effect of short-term factor on face perceptual processing, we manipulated perceptual adaptation in three experiments and investigated participants’ face race perception and discrimination. In Experiment 1, 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 2 and experiment 3. In Experiment 2, we examined the effects of perceptual adaptation on face race categorization performance by presenting the ambiguous-race faces after prolonged exposure (5 seconds) to a Caucasian or an Asian face. Results showed that prolonged exposure to Asian faces causes the identical ambiguous-race morphed faces to appear distinctly Caucasian, vice versa. Furthermore, the identical ambiguous-race morphed faces were categorized faster when the faces were perceived as Caucasian but slower when the faces were perceived as Asian. In experiment 3, we examined the effects of perceptual adaptation on face discrimination by presenting the ambiguous-race faces after prolonged exposure (5 seconds) to a Caucasian or an Asian face. Results showed that the identical ambiguous-race morphed faces were discriminated more accurate when the faces were perceived as Asian but less accurate when the faces were perceived as Caucasian. Collectively, these findings indicate that the short-term, perceptual adaptation may affect participants’ face race categorization and perceptual discrimination, suggesting social-cognitive factors also play a role in the ORE.

Key words: race categorization, perceptual discrimination, other race effect, facial perception