Syntactic Accuracy in Sentence Production: The Case of Gender Disagreement in Italian Language-Impaired and Unimpaired Speakers

We report three experiments with language-impaired and unimpaired speakers of Italian, assessing: (1) whether nonsyntactic (both conceptual and morphophonological) information is used in encoding the syntactic structure of a sentence; and (2) whether the integration of syntactic and non-syntactic information can be differentially impaired in Broca's aphasics. In all the experiments, gender agreement errors between a noun, subject of the sentence, and a predicative adjective were induced by presenting participants with sentence fragments to complete. The first experiment assessed the role of conceptual information. The second experiment investigated whether agreement is disrupted by the presence of another noun with different gender in the subject noun phrase. In the last experiment, we assessed whether morphophonological cues are used. We found that both populations used nonsyntactic information (both conceptual and morphophonological). However, patients were disrupted to a greater extent than normals by the presence of a gender mismatching noun in the subject noun phrase. The results are discussed in terms of how information integration during production is achieved and how it can be disrupted in aphasia.