Published online by Cambridge University Press: 25 July 2013
This study investigates the extent to which the production of complex morphosyntactic structures can be modulated in agrammatic speakers by utilizing a syntactic priming paradigm. Italian clitic pronouns (varying in morphosyntactic complexity) were chosen as the focal linguistic structure under investigation to test hypotheses based on alternative theories. Three experiments were performed. Experiment 1 analyzed clitic production in spontaneous speech. Experiments 2 and 3 used syntactic priming to prime the production of direct- and indirect-object clitics in finite and in restructuring sentences. These structures critically require different clitic positions (finite sentences: before the finite verb; restructuring sentences: before or after the verbal complex). The pattern of results shows that agrammatic speakers are impaired in clitic production. However, they show that the deficit is quantitative rather than qualitative, suggesting residual sensitivity despite the poor performance. The findings demonstrate that agrammatic (and control) speakers show a positive effect of syntactic priming across clitic types, suggesting that agrammatism can be characterized in terms of a linguistic processing deficit owing to increased processing demands for complex linguistic structures. Specifically, it is suggested that morphosyntactic complexity modulates both the level of impairment and the effect of priming for these grammatical structures.