Assessing Verb-Argument Structure and Syntactic Complexity in Aphasia with the Italian Version of the Northwestern Assessment of Verbs and Sentences (NAVS-I)

EasyChair Preprint no. 6507

Abstract

Verb production in agrammatic aphasia is more impaired for verbs with complex (vs. simple) verb-argument structure (VAS), i.e., 2- and 3-argument verbs are harder to process than 1-argument verbs; furthermore, verbs carrying optional arguments are assumed to be harder than verbs selecting for obligatory arguments. In agrammatism, production of non-canonical (e.g., Object-Verb-Subject (OVS)) sentences is more impaired than that of canonical (SVO) sentences. The Northwestern Assessment of Verbs and Sentences (NAVS) was developed to evaluate verb and sentence production and comprehension in aphasia. For the Italian version of the NAVS, forty-four healthy participants and 28 participants with aphasia (16 fluent, 12 nonfluent) took part in the study. Mixed-effects regressions showed, for the nonfluent group, better production of 1- vs. 2-argument verbs on the VNT, and no effects of VAS complexity on the ASPT. For the fluent group, no effect of argument number was found. Argument optionality had no effect in either group. Both fluent and nonfluent groups showed better production and comprehension of canonical (vs. non-canonical) sentences. In production, the canonical advantage was greater for longer than shorter sentences for nonfluent participants, and for people with lesser (vs. greater) aphasia severity in the fluent group. Comprehension of object-relative sentences was significantly more impaired than that of subject-relative sentences only in nonfluent participants. Results indicate that verb production is affected by VAS complexity in nonfluent aphasia, and that optionally transitive verbs are not stored with multiple argument frames in the lexicon. Syntactic complexity affected sentence production and comprehension in both fluent and nonfluent aphasia. However, a canonical advantage in production was found only in mild (residual) forms of fluent aphasia, i.e., when lexical retrieval is relatively spared.

Keyphrases: Aphasia assessment, sentence comprehension, sentence production, verb argument structure

@Booklet{EasyChair:6507,
  author = {Elena Barbieri and Claudio Luzzatti and Cynthia K. Thompson},
  title = {Assessing Verb-Argument Structure and Syntactic Complexity in Aphasia with the Italian Version of the Northwestern Assessment of Verbs and Sentences (NAVS-I)},
  howpublished = {EasyChair Preprint no. 6507},

  year = {EasyChair, 2021}}