The Production of Gesture and Speech by People With Aphasia: Influence of Communicative Constraints

Purpose: People with aphasia (PWA) use different kinds of gesture spontaneously when they communicate. Although there is evidence that the nature of the communicative task influences the linguistic performance of PWA, so far little is known about the influence of the communicative task on the production of gestures by PWA. We aimed to investigate the influence of varying communicative constraints on the production of gesture and spoken expression by PWA in comparison to persons without language impairment. Method: Twenty-six PWA with varying aphasia severities and 26 control participants (CP) without language impairment participated in the study. Spoken expression and gesture production were investigated in 2 different tasks: (a) spontaneous conversation about topics of daily living and (b) a cartoon narration task, that is, retellings of short cartoon clips. The frequencies of words and gestures as well as of different gesture types produced by the participants were analyzed and tested for potential effects of group and task. Results: Main results for task effects revealed that PWA and CP used more iconic gestures and pantomimes in the cartoon narration task than in spontaneous conversation. Metaphoric gestures, deictic gestures, number gestures, and emblems were more frequently used in spontaneous conversation than in cartoon narrations by both participant groups. Group effects show that, in both tasks, PWA's gesture-to-word ratios were higher than those for the CP. Furthermore, PWA produced more interactive gestures than the CP in both tasks, as well as more number gestures and pantomimes in spontaneous conversation. Conclusions: The current results suggest that PWA use gestures to compensate for their verbal limitations under varying communicative constraints. The properties of the communicative task influence the use of different gesture types in people with and without aphasia. Thus, the influence of communicative constraints needs to be consdered when assessing PWA's multimodal communicative abilities.