The influence of instrumentality and name-relation to a noun on verb comprehension in Dutch aphasic speakers

Abstract

Background : Different studies have examined the effect of verb type on comprehension, generally in non-fluent aphasic speakers. The current study includes the data of fluent aphasic speakers as well and considers the effect of conceptual and phonological factors on verb comprehension. Aims : The role of the factors instrumentality and name-relation to a noun were studied. Both factors take the relation between nouns and verbs into account. Instrumentality concerns the conceptual relation between verbs and nouns, whereas name-relation expresses the phonological relation between these two. Methods & Procedures : A total of 13 non-fluent aphasic speakers and 11 fluent aphasic speakers performed a word-to-picture matching task. This task consists of 60 items: 20 target verbs are non-instrumental, 40 verbs are instrumental. Instrumental verbs are defined as verbs referring to actions for which an instrument is required in order to perform the action. Within the group of instrumental verbs, 20 are name-related to the corresponding instrument, whereas for the other 20 verbs no such relation exists. Results on the test were analysed both quantitatively and qualitatively. Outcomes & Results : Both factors were of influence on the verb comprehension scores, but in different ways in the two subject groups. Instrumentality played a role for the non-fluent aphasic speakers: they were significantly better at comprehending non-name-related instrumental verbs as compared to the other types of verbs. Name-relation to a noun had a negative effect on the scores of the fluent aphasic speakers: they had a significantly lower score on name-related instrumental verbs, than on non-name-related instrumental verbs. Conclusions : The factors instrumentality and name-relation to a noun influenced verb comprehension, but not in the same way in both types of aphasic speakers. It is discussed that this is due to different underlying disorders that lead to verb comprehension problems.