Effects of visibility between speaker and listener on gesture production: Some gestures are meant to be seen

Do speakers gesture to benefit their listeners? This study examined whether speakers use gestures differently when those gestures have the potential to communicate and when they do not. Participants watched an animated cartoon and narrated the cartoon story to a listener in two parts: one part in normal face-to-face interaction and one part with visibility between speaker and listener blocked by a screen. The session was videotaped with a hidden camera. Gestures were identified and classified into two categories: representational gestures, which are gestures that depict semantic content related to speech by virtue of handshape, placement, or motion, and beat gestures, which are simple, rhythmic gestures that do not convey semantic content. Speakers produced representational gestures at a higher rate in the face-to-face condition; however, they continued to produce some representational gestures in the screen condition, when their listeners could not see the gestures. Speakers produced beat gestures at comparable rates under both conditions. The findings suggest that gestures serve both speaker-internal and communicative functions. (C) 2001 Academic Press.