Language & Cognition Seminar - Dr Samuel Evans

Visual and auditory language signals activate many of the same brain regions. It has often been assumed that the same linguistic processes are computed in these areas and that this reflects the activity of a modality independent language network. However, to date this assumption has rarely been tested. In this talk, I will present the results of two functional Magnetic Resonance Imaging studies that used Representational Similarity Analysis to ask what kind of information is encoded in brain regions jointly activated by auditory and visual language signals. In the first of these studies, we tested for shared neural representations for phonology evoked by auditory and visual speech (lipreading) and in the second, for shared semantic representations for auditory speech and sign language (BSL). We show that the extent of shared representation is relatively limited and dependent on both the precise visual language and linguistic process investigated. In conclusion, these studies reveal the need to review our assumptions concerning the extent of shared neural representations for auditory and dynamic visual language signals.