PRONOUN PRODUCTION IN AGRAMMATIC SPEAKERS - PATTERNS OF USE AND AVOIDANCE IN CONTEXT NEUTRAL SENTENCES

This study examined pronoun production in the sentences of agrammatic speakers. A Sentence Generation task that asks each subject to create a sentence from a given, uninflected transitive verb was administered to nine agrammatic aphasics and 20 matched normal control speakers. Se ntences that contained at least two arguments of the verb, one PreVerb NP and one PostVerb NP, were examined to determine what proportion of each NP position was filled by the following NP types: Pronoun, Gener al Noun, or Specific NP (e.g. 'he', 'man', or 'teacher', respectively) . The normal speakers tended to use pronouns as PreVerb NPs and specif ic lexical terms as PostVerb NPs (Kohn and Pustejovsky 1994). Aphasic performance that was two standard deviations or more from the normal m ean was judged to be abnormal. All but one aphasic subject departed fr om the normal data. The remaining aphasic subjects fell into three def icit groups, each defined by a significant increase in comparison to t he control subjects for one of the three NP types. In each deficit gro up the overall distribution of NP types by NP position suggested an un derlying cause, for which pronoun use figured centrally into the expla nation. Increased Pronoun use was associated with a decreased use of S pecific NPs, suggesting impaired word finding at the level of accessin g sentence-based, as opposed to category-based, lexical associations. Increased use of General Nouns was associated with a severe avoidance of pronouns, while an increased use of Specific NPs was associated wit h milder pronoun avoidance. The tendency for the aphasic subjects to p roduce anomalous sentences (i.e. with syntactic and/or semantic errors ) provided additional insight into the mechanisms underlying the respo nse to pronouns in each deficit group.