How modality processing differences affect cross-modal nonspatial repetition inhibition.

Although previous studies have demonstrated that identity-based repetition inhibition could occur across modalities, whether the modality processing difference or attentional set caused differences between the unimodal and cross-modal conditions was unknown. To investigate this question in both visual-auditory and auditory-visual patterns, the present study adopted a cross-modal "prime-neutral cue-target" priming paradigm, in which a neutral event was presented between the prime and the target. The relationships of the identities and modalities between the prime and the target were manipulated such that their modalities and identities could either be the same or different. Our results showed that (a) identity-based repetition inhibition occurred under both unimodal and cross-modal conditions, (b) response times to auditory targets were slower than those to visual targets, and (c) identity-based repetition inhibition was larger while discriminating repeated auditory targets than visual targets regardless of whether the prime was visual or auditory. These results suggested that nonspatial repetition inhibition can occur across modalities and that it was not in general larger or smaller than unimodal repetition inhibition, as this difference was due to modality processing differences.