Differential lateralization for words and faces: category or psychophysics

Abstract

& This set of three experiments assessed the influence of dif-ferent psychophysical factors on the lateralization of the N170 event-related potential (ERP) component to words and faces. In all experiments, words elicited a left-lateralized N170, where-as faces elicited a right-lateralized or nonlateralized N170 de-pending on presentation conditions. Experiment 1 showed that lateralization for words (but not for faces) was influenced by spatial frequency. Experiment 2 showed that stimulus presenta-tion time influenced N170 lateralization independently of spa-tial frequency composition. Finally, Experiment 3 showed that stimulus size and resolution did not influence N170 lateraliza-tion, but did influence N170 amplitude, albeit differentially for words and faces. These findings suggest that differential later-alization for words and faces, at least as measured by the N170, is influenced by spatial frequency (words), stimulus presenta