Dataglove Measurement of Joint Angles in Sign Language Handshapes

In sign language research, we understand little about articulatory factors involved in shaping phonemic boundaries or the amount (and articulatory nature) of acceptable phonetic variation between handshapes. To date, there exists no comprehensive analysis of handshape based on the quantitative measurement of joint angles during sign production. The purpose of our work is to develop a methodology for collecting and visualizing quantitative handshape data in an attempt to better understand how handshapes are produced at a phonetic level. In this pursuit, we seek to quantify the flexion and abduction angles of the finger joints using a commercial data glove (CyberGlove; Immersion Inc.). We present calibration procedures used to convert raw glove signals into joint angles. We then implement those procedures and evaluate their ability to accurately predict joint angle. Finally, we provide examples of how our recording techniques might inform current research questions

Brief Report: Visuo-spatial Guidance of Movement during Gesture Imitation and Mirror Drawing in Children with Autism Spectrum Disorders

Thirteen autistic and 14 typically developing children (controls) imitated hand/arm gestures and performed mirror drawing; both tasks assessed ability to reorganize the relationship between spatial goals and the motor commands needed to acquire them. During imitation, children with autism were less accurate than controls in replicating hand shape, hand orientation, and number of constituent limb movements. During shape tracing, children with autism performed accurately with direct visual feedback, but when viewing their hand in a mirror, some children with autism generated fewer errors than controls whereas others performed much worse. Large mirror drawing errors correlated with hand orientation and hand shape errors in imitation, suggesting that visuospatial information processing deficits may contribute importantly to functional motor coordination deficits in autism

Winter Counts as Possible Precursors to Writing

Native Americans of the Great Plains did not have a formal system of writing. These groups did, however, have various types of graphical representation. One such example is the Siouan winter counts, pictures recorded once each winter on buffalo hide (or later on cloth) which served as mnemonic devices for a partial oral history and calendar of the group to which it belonged. Scholars often study the subject matter of these counts in order to gain historic or cultural information about Native groups. Despite the facts that only one important or unusual event is depicted each year, and that the accompanying verbal interpretations can be fraught with complications, these records, along with the phrases memorized and passed down with them, have proven useful in this pursuit However, the purpose of this paper is not to explore the historic significance of these counts, but rather to examine their pictures as symbols of those events. It is this researcher\u27s contention that the pictures used in many of the Siouan winter counts share important characteristics with the precursors of established writing systems, and therefore, could have been precursors to writing

A constraint -based account of handshape contrast in sign languages

The main goal of this dissertation is to explore the nature of contrast in sign language handshapes. I first demonstrate that the distribution of handshape contrasts is not homogeneous, either within or across sign languages. By using a variety of methodologies (examination of dictionary data, elicited data, and psycholinguistic experimentation), I present examples of differences related to type of contrast (distinctive, active, and prominent—following Clements, 2001); position in the lexical substrata (following the work of Ito and Mester, 1995a, and Brentari and Padden, 2001); iconic relationships (e.g. shape, size, arrangement of parts); and cross-linguistic variation (comparing American Sign Language, Swiss German Sign Language, and Hong Kong Sign Language). I also propose that the distributional differences in handshape contrasts can be explained in terms of a confluence of pressures on language. Using the tenets of Optimality Theory (OT), these differences can be explained by determining how various languages—or lexical components within languages—rank constraints related to those pressures. Specifically, I follow Flemming\u27s (2002) version of OT (Dispersion Theory) in which grammars balance the pressures of articulatory ease and perceptual distinctiveness, as well as the desire to maximize the number of contrasts available for word formation. To this, I propose an additional pressure—one to maintain contrasts borrowed into the language from external sources. These external contrasts can be borrowed from other languages (directly from other sign languages, or indirectly from spoken languages via systems such as fingerspelling), or they can be borrowed from visual aspects of the real world