L’alexie sans agraphie : un déficit exemplaire, choyé par les neuropsychologues

Abstract

Alexia without agraphia is the result of a left inferotemporal cortical lesion. This unilateral lesion provokes an almost irrecoverable word reading disability. This anatomical-clinical observation has identified as crucial an area on the left fusiform gyrus, which represents a sort of “letter cranial bump”. This area, located near the left V4, has been labeled the visual word form area (VWFA). The VWFA ensures visual word processing whatever the visual field stimulated. In normal subjects, imaging methods show an activation of the VWFA during reading. In patients, the alexia that follows a VWFA lesion proves that this area is an essential relay for cerebral word reading processing. Therefore, pure alexia is no longer explained by a posterior interhemispheric disconnection.