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

Abstract

The study has systematically investigated how gestures are used in discourse differently between speakers with and without aphasia. Among speakers with aphasia, how gestures differed in several factors, including (1) hemiplegia, (2) aphasia severity, (3) linguistic performances and (4) semantic processing impairment on gesture use were also examined. Gesture analysis using the recently proposed coding system of gestures was conducted in 48 speakers with aphasia and 12 normal speakers to update the normative data of 119 normal speakers in the previous study. The results show that speakers with aphasia produced significantly more gestures than normal speakers. Among speakers with aphasia, the presence of hemiplegia didn't affect the frequency of gesture use. However, those with more severe aphasia, more complete sentences and simple sentences in discourse, verbal semantics processing impairment were found to use gestures more frequently in all discourse tasks. The relationship between gesture and speech in speakers with aphasia, whether gestures were used as compensation in communication and/or assisting lexical retrieval with the presence of language deficits due to aphasia, is discussed.