Syntactic complexity in the presence of an intervener: The case of an Italian speaker with anomia.

Background: A robust finding from language acquisition, adult processing and individuals with language impairment is that certain types of Object Relatives (ORs) and Object Questions (OQs) are more challenging in both production and comprehension compared to their Subject counterpart. Approaches informed by linguistic theory have been proposed to clarify the source of the difficulties with these sentences in people with aphasia, with recent models supporting the idea of a grammatically based resource reduction selectively affecting sentences requiring the processing of an element acting as an intervener. Aims: This work presents new evidence to the study of syntactic competence in people with acquired language disorders, describing in detail the morphosyntactic competence of an Italian speaker with anomia. Methods & Procedures: The clinical diagnosis of anomia in the participant revealed a deficit in lexical retrieval with no deficit at grammatical level. Morphosyntactic competence was investigated through a series of off-line tasks on both comprehension and production. Outcomes & Results: The morphosyntactic abilities of the participant turned out to be for the most part intact with no difficulties such as agrammatism. However, a selective deficit in the computation of certain ORs and OQs emerged. The deficit was selective for structures with an intervener and more specifically for structures in which the featural specification of the intervening subject is included in the one of the displaced object. Conclusions: Syntactic asymmetries emerged in the performance of an individual with anomia, with no apparent morphosyntactic impairment or sign of agrammatism. The deficit of the syntactic computation was selective and compatible with the grammatical Featural Relativized Minimality approach to the difficulties in the computation of sentences with an intervener. The findings presented in this work suggest that the analysis of sentences with an intervener may be a sensitive test for the diagnosis of a syntactic based impairment and that formal linguistic models may offer promising tools for exploring linguistic deficits. KEYWORDS: Anomia; Object Relatives; Object Questions; Syntax; Featural Relativized Minimality; Agrammatism.