Doctoral Dissertation Research:The long and short of linguistic variation:Dual mechanisms of cognitive control in processing phonological variation and the adoption of sound change

Language users readily adapt to linguistic variation, both in the short term -- after exposure to another's speech -- and in the long term as linguistic structures change in the surrounding community. How is an individual's interaction with linguistic variation influenced by the general cognitive strategies used to resolve competition in the environment? In a dual mechanisms framework, cognitive control -- the mechanisms engaged to resolve conflict and regulate expectations -- is divided into two interrelated strategies: proactive and reactive control. Study 1 examines how those control strategies influence individual adaptation to distributional changes in speech input, using an experiment simulating sound change in the laboratory. Less habitual engagement of proactive and reactive control strategies is hypothesized to facilitate the integration of phonological variation. Study 2 then translates the same behavioral tasks to the field in a community-based study examining language variation on a larger scale: sound changes-in-progress (as when 'wait' sounds more like 'wheat'). This dissertation complements existing knowledge regarding sound change in Philadelphia by collecting sociolinguistic interviews of Puerto Rican Philadelphians, one of the largest communities outside of Puerto Rico. Interviews are collected from two age groups and two neighborhood groups based on demographic makeup (proportion of Black and White Philadelphians) to document how one?s immediate community influences participation in three socially-stratified sound changes-in-progress. The same participants then complete the three behavioral tasks from Study 1 (AX-CPT, a modified Stroop paradigm, and an n-back task with lures), permitting a regression analysis of how control strategies modulate their adoption of changes-in-progress. This is one of the first studies to explicitly link dual mechanisms of cognitive control to language processing. It is unique in applying these strategies both to simulated sound change in the laboratory and real-world sound change in the community, documenting the speech of an understudied population and providing a unified account of how social and cognitive factors interact in language use.