Aspects of rhythm in gesture and speech

This article investigates the rhythmic relationship between gesture and speech. Four subjects were filmed in natural conversations with friends. From the resulting videos, several thousand time-stamped annotations pertaining to rhythm were manually recorded in a digital annotation tool, and exported for statistical analysis. They revealed a rich rhythmic relationship between the hands, head, and voice. Each articulator produced pikes (a general term for short, distinctive expressions, regardless of the modality) in complex synchrony with other articulators. Even eyeblinks were synchronized, with eyelids held closed until reopening on the rhythmic beat, akin to a pre-stroke hold before a gestural stroke. Average tempos similar to previously reported natural human tempos — e.g. Fraisse’s (1982) 600 ms figure — were found in hands, head, and speech, although hands tended to move most quickly and speech most slowly. All three also shared a common tempo of around a third of a second, perhaps to synchronize inter-articulator meeting points. These findings lend empirical weight to earlier observations of a rhythmic relationship between gesture and speech, providing support for the theory of a common cognitive origin of the two modalities.