IMPLICIT SUBLEXICAL PHONOLOGICAL PROCESSING IN AN ACQUIRED DYSLEXIC PATIENT

We report a case study of an acquired dyslexic subject, who on tasks standardly used to assess acquired dyslexia showed no evidence of having any access to sublexical phonological information. However, on a lexical decision task, he showed normal effects of spelling regularity for low-frequency words. Since this effect is typically attributed to the use of sublexical phonological information in word recognition, it appears that sublexical phonological processing is occurring for this subject. The spelling regularity effect is discussed with respect to models of written word recognition and to acquired dyslexia. It is suggested that the reason for the discrepancy in test results may be that the types of explicit tasks previously used in the neuropsychological literature on dyslexia, which require conscious awareness of phonological representations, are not sensitive to implicit processing.