The Contributions of Spatial Processing and Selective Attention to the Deficits in Patients with Spatial Neglect and Neglect Dyslexia

Abstract

Many patients with right hemisphere stroke fail to read words closest to the left margin of text and/or commit within-word errors on left-sided letters while correctly reading right-sided letters, a condition known as neglect dyslexia. These patients also show non-spatial deficits of selective attention, which may be a contributing factor to these errors. The purpose of this study was to determine the relative contributions of spatial processing deficits and selective attention deficits on reading errors in neglect dyslexia. In Experiment 1, we replicated studies that showed poorer reading accuracy for words when presented alongside a competitive distractor word than when presented solitarily. This deficit was larger for words on the left. In Experiment 2, we modified the paradigm so that the target word was positioned centrally at fixation in all conditions, in an effort to minimize spatial effects. We found that patients performed worse under conditions with a distractor word regardless of the side on which the distractor was presented. These findings suggest that the errors in neglect dyslexia are at least partly due to a selective attention deficit.