The influence of body posture and gesture on the evaluation of verbal utterances addressment and comprehensibility

During everyday communication co-speech gestures represent a ubiquitous tool to underpin the verbal content of a message. In addition to gestures, other non-verbal information, such as the direction in which a speaker’s body is oriented, is particularly important during face-to-face interaction. However, the influence of bodily orientation (frontal vs. lateral) and gestures on the evaluation of comprehensibility and addressment of verbal utterances has not been investigated, so far. It might be hypothesized that meaningbearing gesture in a frontal context improves the comprehensibility and the addressment of a verbal message. In fact, we found a significant interaction of the factors gesture (gesture/no-gesture) and body orientation (frontal/lateral) for the evaluation of addressment, indicating that frontally presented co-verbal gesture was evaluated as most addressing. Though for comprehensibility the interaction was not sig., comprehensibility was evaluated highest in the context of frontally presented co-verbal gesture. Gesture seems to have a general positive effect on comprehension as indicated by higher comprehension scores and faster evaluations. However, the main effect of body orientation on evaluations suggests that a frontal perspective additionally seems to contribute to comprehension. These data demonstrate the importance of body orientation and gesture on the evaluation of the comprehension and addressment of verbal utterances. Our results suggest a beneficial effect for frontally presented co-speech gesture.