Positional dyslexia.

Position-specific errors in word reading are usually associated with neglect or visual extinction on the same side as the reading problem. In this study, two patients with left-hemisphere lesions showed visual extinction on the right but reading difficulty on the left side of words and pseudowords. Further study of one patient revealed that he also had problems reading the beginning of words presented tachistoscopically or in vertical orientation. In addition, the positional difficulty was apparent when he named the letters in words. The pattern of results indicates that the positional dyslexia in these patients was not likely attributable to general deficits in visual perception or attention but may have reflected a disorder at a later stage of letter processing.