Modifications in Sign Under Conditions of Impeded Visibility

Abstract

This study investigated the effects of reduced visibility on the distance of signing hands from the bodies of adult signers who are deaf and on their rates of sign production. Subjects were videotaped as they signed with partners in each of three experimental conditions: unimpeded, moderately impeded, and severely impeded visibility. Visual impedance was created by placing screens between signing partners. The distance of a hand from the body, in terms of lateral, vertical, and forward-depth dimensions, was determined from digitized measurements of single video frames randomly selected from those in which the subject was actively signing. Sign rate was calculated as the number of signs produced in a given segment of time. Signs produced in the severely impeded visibility condition were found to be made at a slower rate and with a mean hand position further forward and vertically higher than signs produced in the unimpeded visibility condition.

The influence of visual feedback and register changes on sign language production: A kinematic study with deaf signers

“…In contrast, increasing the size of signing space may only increase comprehensibility in visual “noise” for sign perceivers, not for sign producers. Naeve, Siegel, and Clay (1992) found that when the perception of signing was impeded by a large screen between conversational partners, participants produced signs with a greater mean vertical distance and with greater forward motion, just as we observed for shouted signing (see Table 1 and Figure 4). Visual impedance from a screen does not impair the signer’s view of his or her own hands, whereas the presence of environmental noise impairs the speaker’s ability to hear his or her own voice.…”

Gesture links language and cognition for spoken and signed languages

“…Because co-sign gesture and sign are both produced in the same perceptual channel, they are both impacted by the clarity of the signal, that is, whether the signer and addressee can easily see each other. When visibility is reduced (for example, by a semi-transparent barrier), signers tend to produce slower and larger signing-the manual equivalent of shouting 122,123 . The production of signs, co-sign gesture, and independent gestures (for example, pantomimes or emblems) are all similarly impacted by reduced visibility.…”

Viewing angle matters in British Sign Language processing

“…Other studies have altered the environment, e.g. impeding visibility with barriers 12 , or limited the receiver’s perception by using goggles or blindfolds to prevent self-monitoring 13 . Aside from research on the intelligibility of signed language videos on early mobile phones with poor quality 14 , the aforementioned lab-generated stimuli and scenarios are somewhat artificial, telling us more about visual processing than everyday challenges of real-life signed language comprehension.…”