Signed Languages: Discoveries from International Research

Why Not GIVE-US: An Articulatory Constraint in Signed Languages

Why Not GIVE-US: An Articulatory Constraint in Signed Languages Gaurav Mathur and Christian Rathmann Movement constitutes one of the parameters in a signed language (along with parameters of location, handshape, and orientation) that correspond to phonemes in spoken languages. Traditionally, movement has been defined in perceptual terms. For example, Stokoe (1960) and Stokoe, Casterline , and Croneberg (1965) use terms like up and down to describe some of the possible movements in signed languages. However, we propose that movement can and should be described in articulatory terms, as has been done in phonetics for spoken languages. Loncke (1985) points out that some gestures are, from an articulatory point of view, more difficult to sign than others. For example, it is a hard task to hold an A handshape oriented to the ipsilateral side. To make this gesture, a signer would pronate the forearm while performing an adduction of the wrist. However, it would be a much easier task if the A-hand were oriented to the contralateral side. One does not need to know any signed language to understand this fact because the difficulty results from a universal property of the physiology of the hand and the arm. In an analysis of the handshapes of American and Taiwanese sign languages from a physiological point of view, Ann (1996) uncovers a correlation between the physiological complexity of the handshape and its relative frequency in the sign language lexicon. We are interested in a similar approach not only for the hand but also for the entire arm, and we take one further step by proposing that articulatory-based units actually play a role at a more abstract level of grammar and not just in physiology. The sonority hierarchy proposed by Sandler (1993, 254) serves as a motivation for taking this approach. The purpose of the sonority hierarchy is to define the degree of perceivability of phonetic-phonological information. 1 The authors’ last names for this paper have been alphabetically ordered. We would like to thank Gene Mirus and our consultants who have been enthusiastic about our project. We are especially grateful to Richard Meier and Adrianne Cheek for their helpful comments on an earlier draft of this paper, and we would like to thank Richard Meier and Sigmund Prillwitz for letting us use their lab resources at the University of Texas in Austin and at the Universität Hamburg, respectively. The illustrations in this chapter are by Christian Rathmann and may not be reproduced without his consent. As noted by Sandler, contacting location is least perceivable whereas path movement with trilled internal movement is most perceivable. 1: contacting location 2: plain location 3: location with trilled internal movement 4: contacting movement 5: non-path movement with internal movement 6: path movement 7: path movement with internal movement 8: path movement with trilled internal movement The hierarchy would receive a more natural explanation if we translated these terms into joint-based articulatory terms. Each joint would have one value higher than the joint directly below in the arm. For example, the highest joint, the shoulder, would have a value of 7; shoulder and forearm twist, 6; elbow, 5; radio-ulnar, 4; wrist, 3; metacarpophalangeal (K2), 2; and proximal interphalangeal (K1), 1. One would add the values of all the joints that are involved in the sign and would also factor into the formula the number of degrees (0–90 degrees) that the active joints are extended or flexed. The final result of the formula would determine the relative “sonority” value of the sign. This sonority would be analogous to energy expenditure. See Brentari (1998, 218) for a similar proposal. Although this sonority formula has yet to be tested, it is just one potential application that illustrates the usefulness if not the necessity of an articulatory -based approach toward sign phonetics. If this approach is correct, we expect that some articulatory constraints would be defined in terms of constraints on joint movement. We believe that such constraints interact with verb agreement. In this paper, we investigate one part of verb agreement in four signed languages to shed light on the nature of these joint constraints. These four signed languages are American Sign Language (ASL), Australian Sign Language (Auslan), German Sign Language (DGS), and Russian Sign Language (RSL).1 In this paper, we provide background information on the verb agreement of the signed languages that we are interested in. Then, we explain the procedure of our study and follow that...