| Abstract: | We report a case study of a patient, NY, who developed features of an attentional dyslexia as one manifestation of a variant of Alzheimer's disease in which parieto-occipital areas are most affected. Although able to read single w ords w ithout diffi culty, N Y w as unable to read text. W hen reading two-word displays, he showed an apparent tendency for letters from one word to intrude into the other. Investigation of this phenomenon demonstrated that these errors were due to letter migration as opposed to non-contextual substitution and that the incidence of m igrations decreased when the two words appeared in different case letters. This reduction in interference by physical dissimilarity among the display elements differentiates NY from the two cases described in the original account of attentional dyslexia (Shallice & Warrington, 1977). Analyses of NY's error patterns pointed to the loss of location information as a significant factor in the generation of his migration errors. |
