Following our work on the relationship between eyebrow movements and the fundamental frequency of the voice, this article presents the results of a study on the temporal location of rapid eyebrow movements with respect to speaking turns during dialogue. We used an automatic movement-acquisition system coupled with the simultaneous, synchronized recording of the vocal production. This procedure permits an objective analysis of eyebrow movements in relation to the vocal production. The data obtained show that the speakers ' rapid eyebrow movements were associated with turn-taking (occurring on or before speaking turn onset). These findings suggest that rapid eyebrow movements are mainly linked to motivation and the intention to communicate.