Minimal structures in aphasia: A study on agreement and movement in a non-fluent aphasic speaker

To investigate the linguistic competence of a non-fluent aphasic speaker we focus on certain properties of the patient’s deficit in the functional lexicon, and ascribe occurrences of non-standard use to defective syntactic computation. By manipulating the position of constituents, we tested agreement in sentences with post-verbal subjects and the patient’s ability to detect errors induced by different elements in attraction configurations. The results show clear asymmetries in grammaticality judgments of the different agreement conditions. A deficit in the computation of agreement in sentences with post-verbal subjects was reported, indicating the fragile nature of post-verbal subject agreement. In the experiment on attraction we found a clear impairment, with attraction induced by linear intervention of a prepositional modifier. However, the patient does not regard clitics as potential interveners in the SubjV agreement relation, in accordance with the view that there is no evidence for the weak status of clitic pronouns in Italian. By investigating the finer properties of functional elements we hope to show the extent to which certain characteristics of aphasic speech may be attributed to a possible reduction in the ability to process the finer structures of linguistic computations. A deficit in non-local configurations (the establishment of a relation over an intervening argument), along the lines of recent theoretical developments, was attested.