Neglect Dyslexia for Numbers? A Case Report

Abstract

We report the case study of a patient (YM) with a specific number reading deficit, but with fairly preserved number comprehension and calculation. YM exhibits a spatial error pattern akin to neglect dyslexia, making most of his reading errors and perseverations on the leftmost digit of any number. This and a strong effect of visual similarity on errors suggest a visual deficit. Yet number syntax is preserved: most productions are legal number names, and less errors are observed on digits 0 and 1 when they bear a silent or syntactic role. On the basis of a detailed account of the deficit, we propose a revision of McCloskey, Sokol, and Goodman's (1986) model of number reading. We further discuss the apparent contradiction between the symbolic and the spatial aspects of YM's reading deficit, and the adequacy of the concept of neglect dyslexia.