Violating the phonotactic properties of American Sign Language to create illegal pseudosigns

Abstract

This study aimed to develop a set of visual-manual stimuli that varied in structure, phonotactic permissibility, and lexicality, to be used in future brain imaging studies of sign language learning. By developing a set of illegal pseudosigns as part of these stimulus sets, we also the first steps towards validating some of the hypothesized phonotactic constraints for American Sign Language. Possible phonotactic constraints and violations were identified with a group of native ASL signers and cross-referenced with published inventories of ASL. These violations were systematically applied to a set of real ASL signs. English speaking non-signing participants rated these illegal pseudosigns — along with a set of legal pseudosigns, a set of emblematic gestures, and a set of ASL signs — on a scale of meaningfulness and decided if each stimulus was ASL, yes or no. Interestingly, participants perceived some ASL signs and pseudosigns as meaningful, which may reflect that they interpreted these stimuli as pantomime or emblems. Overall, participants gave lower average meaningfulness ratings to illegal pseudosigns than legal pseudosigns, and were more likely to rate legal pseudosigns than illegal pseudosigns as ASL, suggesting that illegal pseudosigns are perceived as less plausible forms even to those naïve to signed languages. This suggests that the rules governing the formation of ASL appear to respect visual-manual patterns that are inherently interpreted as potentially meaningful or communicative.