Abstract
A new classification of nonaphasic (isolated) alexia or agraphia was proposed. This classification is different from the conventional one in the following points : (i) Non-classic type (nonsplenium type) pure alexia is divided into fusiform type and (posterior) inferior occipital type. Fusiform type is characterized by pure alexia particularly for kanji, or more generally, pure alexia for words, whereas inferior occipital type pure alexia is characterized by pure alexia particularly for kana, or more generally, pure alexia for letters, (ii) The responsible lesion of alexia with agraphia is localized in the left mid fusiform/posterior inferior temporal gyri (Area 37) . A lesion more medial to it can cause fusiform type pure alexia, and a lesion more dorsal and lateral to it (posterior middle temporal gyrus, Area 21/37) can cause pure agraphia for kanji, and (iii) The precise lesion localization of angular alexia with agraphia involves not only the angular gyrus but also the adjacent lateral occipital gyri : damage to the angular gyrus alone can yield pure agraphia.
