Heng (Sora) Yin
Neutralization and Homophony in Phonological Learning
One of the central tasks of linguistic theories is to identify and formalize the driving forces behind language change and variation in speech patterns. Previous research has centered around the debate on whether such forces could arise from learning pressures, e.g., patterns that are harder to learn may be cross-linguistically rare since they are less likely to be transmitted over generations (e.g., Wilson, 2006); or from environmental selections, e.g., for patterns that are functionally more effective for communication (e.g., Wedel, 2006). My thesis will contribute to this debate by offering a more integrated perspective—while our preference for learning easier patterns, as a universal constraint, plays a vital role in shaping our speech, the learnability preference itself could in some cases trace its roots back to our functional needs, e.g., our tendency to avoid homophones for preventing ambiguous speech.
Typologically, new pieces of evidence from previously understudied languages have suggested that our speech patterns and lexicon could be tightly linked to each other, due to factors such as homophony avoidance (e.g., Silverman, 2010 on Korean; Kaplan & Muratani, 2015 on Japanese). However, current phonological theories, with their early development deeply rooted in phonology of Western languages, are still disconnected with these new cross-linguistic findings. Thus, my thesis seeks to bridge this gap by incorporating the under-researched languages into theory building, using typological methods and formal analysis. The study takes an even more novel approach to explain the typological data from a learning perspective, by testing whether the learnability of certain speech patterns could be affected by the properties of word meaning and our need to avoid homophones, through learning experiments and computational modeling. Ultimately, the study contributes to our understanding of how languages evolve towards an effective communication system under both formal and functional pressures.