Acoustic specification of upper limb movement in voicing

Hand gestures communicate through the visual information created by movement. Recently, we found that there are also direct biomechanical effects of high-impetus upper limb movementon voice acoustics. Here we explored whether listeners could detect information about movement in the voicing of another person. In this exploratory study, participants listened to a recorded vocalizer who was simultaneously producing low-(wrist movement) or high-(armmovement) impetus movements at three different tempos. Listeners were asked to synchronize their own movement (wrist or arm movement) with the vocalizer. Listeners coupled with the frequency of the vocalizer arm (but not wrist) movements, and showed phase-coupling with vocalizer arm (but not wrist) movements. However, we found that this synchronization occurred regardless of whether the listener was moving their wrist or arm. This study shows that, in principle, there is acoustic specification of arm movements in voicing, but not wrist movements. These results, if replicated, provide novel insight into the possible interpersonal functions of gesture acoustics, which may lie in communicating bodily states