Features of aphasic gesturing--an exploratory study of features in gestures produced by persons with and without aphasia.

The purpose of this study was to see how features of gestures produced by persons with aphasia (PWA) are affected and to relate the findings to possible underlying factors. Spontaneous gestures were studied in two contexts: (i) associated with the production of nouns and verbs and (ii) in relation to word finding or production difficulties. The method involved assembling two datasets of co-speech gestures, produced by PWA and by persons without aphasia and to code the gestures for a number of features of expression and content. Features that were affected in the Aphasia dataset were gaze, head movements, hand use and semantic features. The results point to possibly converging explanations, such as generally lower semantic complexity as a direct effect of the aphasia, more cognitive effort and/or a greater dependence on one-hand gestures leading more indirectly to increased gaze aversion, more head shakes and lower complexity in gestures in PWA.