Interaction of attentional and lexical processes in neglect dyslexia

Abstract

Two cases of “left” neglect dyslexia are examined. The two patients show qualitatively similar problems of reading behaviour, although they differ quantitatively in terms of the exposure durations under which neglect dyslexia is manifest. Like other neglect patients documented in the literature, the two patients made mainly substitution errors to the left-hand letter in words, tending to misname the word as a neighbour of similar length. Unlike some patients, the two patients here showed lexical effects (i.e. they performed better with words than with nonwords, and they found words with many orthographic neighbours more difficult to identify than those with few orthographic neighbours). In addition, the patients were susceptible to attempts to manipulate the locus of attention, they were induced into producing addition errors by placing a hash at the left-hand end of letter strings, and their neglect reflected the position of the letter in the string rather than in the visual field. The argument is made that neglect dyslexia may result from a failure in the interplay between lexical and attentional processes in word recognition.