The Phonetics of Head and Body Movement in the Realization of American Sign Language Signs

Because the primary articulators for sign languages are the hands, sign phonology and phonetics have focused mainly on them and treated other articulators as passive targets. However, there is abundant research on the role of nonmanual articulators in sign language grammar and prosody. The current study examines how hand and head/body movements are coordinated to realize phonetic targets.

Kinematic data were collected from 5 deaf American Sign Language (ASL) signers to allow the analysis of movements of the hands, head and body during signing. In particular, we examine how the chin, forehead and torso move during the production of ASL signs at those three phonological locations.

Our findings suggest that for signs with a lexical movement toward the head, the forehead and chin move to facilitate convergence with the hand. By comparison, the torso does not move to facilitate convergence with the hand for signs located at the torso.

These results imply that the nonmanual articulators serve a phonetic as well as a grammatical or prosodic role in sign languages. Future models of sign phonetics and phonology should take into consideration the movements of the nonmanual articulators in the realization of signs.