The Listener in Language Change

Language changes constantly, in ways that can be constrained by factors both language-internal, such as word frequency, and language-external, such as social attitudes. A major challenge for linguistic theory is to give a unified explanation of these constraints on language change. In this dissertation, I argue that this challenge can be addressed by looking to spoken language perception, where passive but powerful perceptual biases give rise to many similar constraints on how listeners update the cognitive representations they draw upon for language use.

I present an approach to language change in which perceptual biases in the listener play a central role. I ground this approach in an exemplar-based computational model, which is able to recreate empirically-observed general properties of sound change. I then test the approach by integrating experimentally-supported perceptual biases with computational modeling and novel corpus methods across two studies. In the first study, I apply the computational model to simulate word-frequency effects in sound change. I show that different word-frequency effects in different kinds of sound change follow from a single perceptual bias, whereby high-frequency words are recognized more easily than low-frequency words when acoustically ambiguous. In the second study, I extend the listener-based approach to the effect of improving interethnic social attitudes on the spread of lexical items across ethnic groups in New Zealand. Drawing on biases in the perception of 'other-accented' words, I make specific predictions for the spread of the tag eh from indigenous Māori to white Pākehā, which I test with novel corpus methods. Taken together, these two studies highlight how passive but powerful perceptual biases in the listener can give a unified explanation of different constraints on language change.

(The format for this open part of the oral exam is a 30-45 minute talk by the PhD candidate followed by questions from those attending, for a total of no more than 75 minutes.   Please arrive promptly!)

University oral exam committee: Dan Jurafsky and Meghan Sumner (co-advisors), Jen Hay, Judith Degen

University oral exam chair: Jay McClelland