How do speakers who move to a new dialect region acquire phonological features of the new dialect? Social factors surely affect this process; for example, the degree to which a speaker wishes to align with the new community will modulate how features associated with that community are acquired. However, linguistic factors - the form of phonological representations, their malleability, and the processes that manipulate them to yield surface forms - must also constrain the types of variation and change available to the individual speaker. Second dialect acquisition data therefore has the potential to shed light on foundational questions in phonological theory.
In this talk I review two prominent models of phonological representation - Generative Phonology and Usage-based Phonology - and set out the predictions each makes regarding how particular kinds of second dialect features ought to be acquired. I then present the results of a sociolinguistic study of mobile adults who acquired their native dialect of English in Canada and later moved to the New York City region, focusing on evidence of change with respect to two features: the cot/caught distinction and height of (aw) in Canadian Raising environments. Finally, I evaluate the predictions set out at the beginning of the talk in light of these findings, arguing that they support a model in which phonological representations are both phonetically rich and linked to social labels.