Séminaire Florence Bouhali
UCSF (San Francisco)
Processing orthography in the visual cortex - Towards a dissociation of phonological and lexico-semantic reading
Learning to read triggers the recycling of neural resources in order to accommodate this cultural skill. In the visual cortex, a reproducible region known as the visual word form area (VWFA) specializes in word recognition, and allows access to both the phonology and the meaning of words. Yet, the exact representations it harbors are unclear, especially as the orthographic units required to access phonology and the lexicon differ in nature. While the lexico-semantic route may operate on letter or open-bigram information, the phonological route requires the identification of multiletter graphemes such as “ch” or “ou” in order to map them onto phonemes. I will present the results of an fMRI study demonstrating that a subregion mesial to the VWFA is involved in processing graphemes specifically. The existence of a "grapheme area", its functional dissociation from the VWFA, and their collaboration bear important implications for the understanding of reading acquisition and of inter-individual differences in reading skills.