Understanding Perceptual Compensation in Sound Change

(National Science Foundation Grant #0949754 + REU supplement, 2010-2013)

Linguists have long hypothesized that sound change–changes in a language over time that alter pronunciation–occurs when a listener misinterprets a speaker and incorporates the misperception into his/her own grammar. However, little is known about the mechanism through which such adjustments occur and mounting evidence is in fact suggesting that listeners are adept at compensating for variation in speech perception and production. From this, it should follow that sound change would occur minimally, contrary to fact. This research investigates the circumstances under which perceptual compensation (PC) fails to correct for variation in speech and how such failures lead to sound change. We approach this question from three perspectives:

• Formal approach: We develop a formal representation of PC (and by extension sound change) to corroborate the experimental findings using Bayesian inference, a statistical tool commonly employed in cognitive science research. This model predicts that the effects of PC may be minimized or even overcome when certain parameters in the model are adjusted; that is, the relative magnitude of compensation is mediated by the properties of a language and the speaker’s prior experience with it.
• Experimental approach: To test the formal theory of PC and its connection to sound change, we carry out laboratory experiments testing the limit and variability of PC effects. The experimental paradigm involves testing listeners’ compensatory responses by varying (1) the frequency of the sounds involved, (2) the context in which the speech signal occurs, and (3) the nature of the speech signal itself.
• Socio-cognitive approach: Language variation and change does not occur in a vacuum. Understanding the social-embedding of language is crucial to revealing the mechanism and trajectory of change. We approach this problem from the perspective of individual variation. We are currently exploring the hypothesis of individual variability in language and speech processing as a conduit for linking the introduction of new variants in language and their eventual spread throughout a community. In particular, we argue that variability in cognitive processing style, which is an important contributing factor to variation in perceptual, and by extension, in production norms across individuals, can be shown to correlate with individual differences in social traits. These social traits may in turn influence how an individual interacts with other members of his/her social network. Taken together, we hypothesize that individuals who are most likely to introduce new variants in a speech community might also be the same individuals who are most likely to be imitated by the rest of speech community due to their personality traits and other social characteristics.

Documentation of the Washo Language

(National Science Foundation DEL Grant #0553675, 2006-2009)

The Washo language, one of the most critically endangered and poorly documented of languages of North America, is now only used by a few elderly speakers who live in several townships near the California Nevada border southeast of Lake Tahoe. Washo is only minimally documented, with no comprehensive grammar or dictionary, except for William Jacobsen’s 1964 doctoral dissertation from the University of California, Berkeley, which contains mainly a phonological and morphosyntactic description of the language. The main objective of this project is a detailed study of the phonetics and phonology (at both the allophonic and morpho-phonological levels) of the Washo language since a solid understanding of the phonetics and phonology of the language is paramount to understanding the other components of the language (e.g., the morpho-syntax, syntax, and discourse). Another priority for this project is the creation of a web-accessible digital archive to make Washo data accessible to scholars and, of equal or greater importance, to the native community itself.

Selected Papers:

• Yu, Alan C. L. To appear. Laryngeal schizophrenia in Washo. In Gene Buckley and Jeff Good (eds.).
• Ryan Bochnak, Timothy Grinsell, and Alan C. L. Yu. 2011. Copula agreement and the stage-level/individual-level distinction in Washo. In Meagan Louie & Alexis Black (eds.), The UBC Working Papers in Linguistics: Proceedings of the 16th Workshop on the Structure and Constituency in the Languages of the Americas. 1-10. (PDF)
• Yu, Alan C. L. 2008. The phonetics of quantity alternation in Washo. Journal of Phonetics 36(3): 508-520.
• Yu, Alan C. L. 2006. Prosodically-conditioned segmental fission in Washo. In Rebecca Cover & Yumi Kim (eds.) The Proceedings of the 31st Annual Meeting of the Berkeley Linguistics Society. 513-524.
• Yu, Alan C. L. 2005 Quantity, stress, and reduplication in Washo. Phonology 22(3): 437-475.