Increased N250 amplitudes for other-race faces reflect more effortful processing at the individual level

Abstract

The N250 and N250r (r for repetition, signaling a difference measure of priming) has been proposed to reflect the activation of perceptual memory representations for individual faces. Increased N250r and N250 amplitudes have been associated with higher levels of familiarity and expertise, respectively. In contrast to these observations, the N250 amplitude has been found to be larger for other-race than own-race faces in recognition memory tasks. This study investigated if these findings were due to increased identity-specific processing demands for other-race relative to own-race faces and whether or not similar results would be obtained for the N250 in a repetition priming paradigm. Only Caucasian participants were available for testing and completed two tasks with Caucasian, African-American, and Chinese faces. In a repetition priming task, participants decided whether or not sequentially presented faces were of the same identity (individuation task) or same race (categorization task). Increased N250 amplitudes were found for African-American and Chinese faces relative to Caucasian faces, replicating previous results in recognition memory tasks. Contrary to the expectation that increased N250 amplitudes for other-race face would be confined to the individuation task, both tasks showed similar results. This could be due to the fact that face identity information needed to be maintained across the sequential presentation of prime and target in both tasks. Increased N250 amplitudes for other-race faces are taken to represent increased neural demands on the identity-specific processing of other-race faces, which are typically processed less holistically and less on the level of the individual.