Cross-modal representation of spoken and written word meaning in left pars triangularis

INTRODUCTION:Representational Similarity Analysis (RSA) provides an opportunity to better understand the nature of the commonalities underlying the semantic processing of different input-modalities. In two event-related fMRI experiments, the primary aim was to localize regions showing a cross-modal semantic similarity effect, and secondary to localize regions showing a semantic similarity effect within a given input modality. METHODS:18 and 20 healthy subjects participated in the first and second experiment respectively. 24 animate entities were used. Based on a feature generation experiment(De Deyne et al.(2008)), the pairwise semantic cosine similarity was calculated for each pair of items(semantic cossimilarity matrix). During fMRI subjects performed a property verification task in spoken and in written modality. fMRI data of the first experiment were modelled using a General Linear Model(GLM). Clusters based on (1)main effect of task and (2)conjunction analysis in the first experiment(uncorrected p<0.001 combined with a cluster-level corrected p