Auditory and Visual Semantic Priming in Lexical Decision: A Comparison Using Event-related Brain Potentials

Abstract
This study compared and contrasted semantic priming in the visual and auditory modalities using event-related brain potentials (ERPs) and behavioural measures (errors and reaction time). Subjects participated in two runs (one visual, one auditory) of a lexical decision task where stimuli were word pairs consisting of “prime” words followed by equal numbers of words semantically related to the primes, words unrelated to the primes, pseudo-words, and nonwords. Subjects made slower responses, made more errors, and their ERPs had larger negative components (N400) to unrelated words than to related words in both modalities. However, the ERP priming effect began earlier, was larger in size, and lasted longer in the auditory modality than in the visual modality. In addition, the lateral distribution of N400 over the scalp differed in the two modalities. It is suggested that there may be overlap in the priming processes that occur in each modality but that these processes are not identical. The results also demonstrated that the N400 component may be specifically responsive to language or potential language events.