On the relation between structural case, determiners, and verbs in agrammatism: a study of Hebrew and Dutch

Background: This study explored the relation between the production of determiners and case markers and the production of verbs and verb inflections in agrammatism. Determiners and case markers require case and therefore depend on the existence of case-assigning constituents. Aims: Since verbs and verb inflections are case assigners, and are impaired in agrammatism, we tested whether the presence of verbs and verb inflection affects the production of determiners and case markers in Dutch and Hebrew agrammatism. Methods & Procedures: A total of 11 Hebrew-speaking and 8 Dutch-speaking individuals with agrammatism participated in picture description and sentence elicitation tasks, and their spontaneous speech was analysed. Outcomes & Results: The production of case-related morphemes was closely connected to the presence of a case assigner in the sentence. In Hebrew, object case was produced correctly 98% of the time, and always when a transitive verb was present in the sentence. In Dutch the production of determiners on the subject was related to the presence of a finite verb. The production of complete object noun phrases related to the presence of a transitive verb. Conclusions: The results indicate that case itself, as well as determiners and case markers, which depend on case, are not impaired in agrammatic production. The apparent deficit is rather tightly related to the deficit in verbs and verb inflection. This suggests that the production of determiners and pronouns should be treated within sentence context, in which a special emphasis should be given to the production of correctly inflected verbs.