Modalitat signada, modalitat parlada i cer-vell: és amodal o multimodal, el llenguatge?

Abstract

Lesions in the perisylvian areas of the left hemisphere give rise to non-fluent or fluent aphasias depending on whether the lesions are frontal or posterior, respectively, both in spoken and signed modalities. Mainly because of this finding, the faculty of language, which is located in those areas, is said to be independent of the modality. However, an assessment of recent research on the subject shows that there is no conclusive evidence for an amodal neural system located in these areas. Cross-modal plasticity in sensory deprivation and a primary multimodal speech system might contribute to explain a neural overlap across both modalities that goes beyond left perisylvian areas whose lateralization depends on the acquisition of speech or sign production in childhood.