Deictic gestures and symbolic gestures produced by adults in an experimental context: hand shapes and hand...

The objective of this study was to gain new insights into the processes underlying gestural communication in adults by examining hand shapes and hand preference patterns associated with different types of gestures. Several communicative situations eliciting pointing gestures and symbolic gestures were presented to 81 participants in an experimental context. Results have highlighted some differences in hand shapes depending on the function of pointing: contrary to results reported in children, the proportion of index-finger gestures was higher in imperative situations than in declarative situations. The distance between the gesturer and the referent was also found to influence hand shapes, proximal pointing being more frequently associated with index-finger gestures than distal pointing. The comparison of hand preferences revealed a greater right-sided asymmetry for declarative pointing than for non-communicative activities, whereas there was no difference between imperative pointing and non-communicative activities, or between symbolic gestures and non-communicative activities. The present study thus sheds some light on the features and the roles of communicative gestures in adults. Results are discussed in relation to the ontogenetic and phylogenetic origins of communication.