Phonetic variation in bilingual speech: A lens for studying the production–comprehension link

• We examine speech production in a corpus of spontaneous Spanish–English codeswitching.
• We find slowed speech rate and cross-language phonological influence preceding codeswitches.
• Using the visual world paradigm, we show codeswitchers exploit these cues in comprehension.
• Demands on the production system can give rise to distributional cues that aid comprehension.
• Codeswitching provides a novel window onto the coupling of production and comprehension.

We exploit the unique phonetic properties of bilingual speech to ask how processes occurring during planning affect speech articulation, and whether listeners can use the phonetic modulations that occur in anticipation of a codeswitch to help restrict their lexical search to the appropriate language. An analysis of spontaneous bilingual codeswitching in the Bangor Miami Corpus (Deuchar, Davies, Herring, Parafita Couto, & Carter, 2014) reveals that in anticipation of switching languages, Spanish–English bilinguals produce slowed speech rate and cross-language phonological influence on consonant voice onset time. A study of speech comprehension using the visual world paradigm demonstrates that bilingual listeners can indeed exploit these low-level phonetic cues to anticipate that a codeswitch is coming and to suppress activation of the non-target language. We discuss the implications of these results for current theories of bilingual language regulation, and situate them in terms of recent proposals relating the coupling of the production and comprehension systems more generally.