A morphological processing deficit in verbs but not in nouns: a case study in a highly inflected language

In this paper we describe a non-fluent aphasic patient who presents a selective impairment in the inflectional morphology of verbs but not of nouns in a highly inflected language, Greek. Furthermore, the patient's impairment was observed in production, but not in comprehension. More specifically, the patient manifested a selective deficit in the production of past-tense forms that do not involve computation of the rule-based aspectual marker. The patient's deficit pattern indicates that morphological processes have to be considered in relation to grammatical class in models of lexical processing. (C) 2002 Published by Elsevier Science Ltd.