Doctoral Dissertation Research: The Effect of Iconicity on Phonetic and Phonological Processes in American Sign Language

Georgetown University, Washington DC

Investigators

Abstract

This dissertation research project examines a difference in the structure of spoken and signed languages. Although they are gestural/visual rather than auditory, signed languages, such as American Sign Language (ASL), are full languages with equal expressive complexity. This has only been recently recognized, however, so ASL research is in its infancy. Comparing signed and spoken languages can reveal the basic cognitive principles that underlie human language. The present study focuses on iconicity, which means that a word or sign resembles its meaning. For example, the sounds in the English word 'pop' mimic a popping noise, and the arrangement of the arm and fingers in the ASL sign 'tree' resemble a tree trunk and branches. Most spoken words are not iconic, but iconic signs are the norm rather than the exception in ASL. This study asks whether iconicity impacts the grammatical patterns of ASL. Do iconic and non-iconic signs function differently? Answering this question will help us better understand how the physical form of a language (speech or sign) impacts its mental organization. To answer this question, grammatical patterns that occur in natural, everyday signing are compared in how they apply to iconic and non-iconic signs. Deaf adult participants are video recorded responding to open-ended prompts about Deaf cultural events. They then watch video clips of ASL signs and sentences in which specific grammatical patterns apply to iconic and non-iconic signs. They respond to each clip, indicating whether the ASL they saw is grammatically correct. If participants apply grammatical patterns differently to iconic versus non-iconic signs, this is evidence that iconicity is part of the grammatical structure of ASL, not just of individual signs, suggesting a fundamental difference from the structure of spoken languages. But if grammatical patterns apply in the same way to iconic and non-iconic signs, this suggests that even though individual signs are more iconic than spoken language words, this property does not impact the language’s grammatical structure. These findings will deepen our understanding of human language beyond what we can learn through spoken language research alone. This knowledge can inform a wide range of applications, such as language acquisition for Deaf babies and training for ASL interpreters. The video narratives collected in the study will be made publicly available and can also serve research in language teaching, interpretation, and Deaf cultural studies. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.