The processing of simple and complex words in an agrammatic patient: evidence from priming

We report the case of an aphasic patient. D.E., who on standard tests is classified as agrammatic. We investigate D.E.'s difficulties in comprehending derived suffixed words by using a combination of on-line tasks which probe the locus of his impairment. These tasks enable us to determine whether the representation and automatic access of derived words are impaired, or whether D.E. has problems integrating these words into the sentential context. We also compare processing of complex words with simple words. We find that the representation and access of derived words is unimpaired and conclude that D.E.'s difficulties with morphologically complex words results from his inability to integrate them into sentence contexts. In contrast, we find that the processing of simple words in isolation is impaired. We suggest that this is because the activation levels of word-competitors decay more slowly than they do for normal subjects.