Semantic information is used by a deep dyslexic to parse compounds.

We report a case study of a 48 year-old patient, J.O., who was tested 20 years after the removal of a tumor in the left temporal-parietal region. This surgery and subsequent radiation resulted in right side paralysis and numerous language problems. Tests of J.O.'s single word reading abilities indicate that she could be classified as a deep dyslexic with over 16% of her errors in word naming having a clear semantic relationship with the target word (Coltheart, 1980). We examined her ability to read compound words aloud and following Libben (1993) we provide evidence that J.O. is a second case in which there is obligatory access of morphological constituents of compound words. These data are discussed within the context of Libben's (1998) compound word processing model.