Do hand gestures increase perceived prominence in naturally produced utterances?

Abstract This study investigates the effect of visually perceived gestures on the overall (multimodal) prominence of naturally occurring stimuli extracted from a multimodal corpus of Maltese conversations. Experiment participants were required to rate the prominence of target words in sentences presented to them as audiovisual and audio-only stimuli. In half of the stimuli, the target word was accompanied by a co-speech hand gesture. The results of the experiment show (i) that words produced with a co-speech gesture were rated as more prominent than words that were produced without one and (ii) that this was the case independently of whether raters could see those gestures (audiovisual condition) or not (audio-only condition). An acoustic analysis of the data shows that the presence of a co-occurring gesture has a significant effect on the pitch of the target vowel. The study suggests that gestures may provide the listener with an additional but not necessary cue to perceiving prominence.