Cross-modal nonspatial repetition inhibition: An ERP study

Previous studies have demonstrated that nonspatial repetition inhibition can occur across modalities. However, the underlying mechanism of such cross-modal nonspatial repetition inhibition is unknown. The present experiment adopted a cross-modal prime-neutral cue-target paradigm in which in consecutive trials the prime and the target were matched or mismatched, not only in identity but also in modality. Meanwhile, event-related potentials (ERPs) to visual and auditory targets were recorded. The present study aimed to answer two questions: which ERP components reflect nonspatial repetition inhibition across modalities, and is the ERP component modality specific or supramodal? The results showed that for visual targets, robust nonspatial repetition inhibition occurred similarly for both unimodal (visual-visual) and cross-modal (audio-visual) target pairings, as indexed by an N400 repetition-induced increment in the typical N400 window but null effects during the N2 epoch. For auditory targets, similar modulation of cross-modal nonspatial repetition inhibition on the auditory-evoked N400 repetition-induced increment was observed. These results suggest that the N400 repetition-induced increment occurs during the N400 epoch that underlies cross-modal nonspatial repetition inhibition and that this N400 component is a supramodal component.