A comparison of co-verbal gestures employment in oral discourse among normal speakers, speakers with fluent aphasia and speakers with non-fluent aphasia

Abstract

The present study compared gestures employment among normal speakers, speakers with fluent aphasia and speakers with non-fluent aphasia. Multimedia data of discourse samples from 23 normal speakers, 23 speakers with fluent aphasia and 21 speakers with non-fluent aphasia were extracted from Cantonese AphasiaBank. A gesture coding system which allows independent annotation of forms and functions was adopted for gestural analysis. While speakers with non-fluent aphasia were found to gesture at the significantly greatest rate, the rate of gesture use of speakers with fluent aphasia did not differ significantly from that of the controls. Different patterns of gesture functions in the 3 speaker groups revealed that the role of gestures in lexical retrieval among the speakers with aphasia is minor while the role of enhancing communication dominates. Among speakers with aphasia, percentage of complete sentences and percentage of dysfluency were found to be the 2 strongest factors to predict gesturing rate. The relationship between gesture production and linguistic abilities and any clinical implication in gesture-based language intervention for speakers with aphasia are discussed.