Looming a loom: evidence for independent access to grammatical and phonological properties in verb retrieval

In principle, a specific deficit in processing verbs relative to nouns might arise as a result of damage to any of several mechanisms involved in speech planning and lexical production. Here we describe a fluent aphasic patient HG who is much worse at retrieving verbs relative to nouns in picture naming and sentence generation, but who retains the ability to produce verbal morphology and even to generate novel verbs productively from nominal roots when she is unable to retrieve appropriate action words (e.g. 'looming' for weaving). Moreover, the results of single word and sentence comprehension tasks suggest that her ability to access lexical forms of verbs is sensitive to their thematic properties. When contrasted with patients who have specific deficits in processing morphosyntactic properties of verbs [J. Neurolinguist. 15 (2002) 265], HG's pattern of performance can be seen as evidence that grammatical properties are functionally distinct from other aspects of lexical representation. We discuss the implications of this dissociation, and of HG's performance specifically, in light of various models of lexical access. (C) 2002 Elsevier Science Ltd. All rights reserved.