Putting Language Switching in Context: Effects of Sentence Context and Interlocutors on Bilingual Switching

Many bilinguals switch languages in daily-life conversations. Although this usually happens within sentence context and with another speaker, most research on the cognitive mechanisms underlying the production of language switches has studied individual words. Here, we examined how context influences both switching frequency and the temporal cost associated with it. Sixty Bulgarian-English bilinguals named pictures in their language of choice without any context, in a sentence context, and in interaction with another (recorded) bilingual. Switching frequency was lower, and costs higher, when bilinguals switched languages with context than without context. This suggests switching costs were not an artifact of tasks without context. Furthermore, both switching frequency and costs correlated across the tasks. In addition, we examined the potential influence of sentence context and the conversation partner. Predictability in sentence context has previously been argued to reduce language competition, which in turn could influence switching. We therefore compared sentences with a predictable or unpredictable target word. As hypothesized, bilinguals were less likely to switch languages when a word was predictable in its sentence context, potentially because words in the other language were less active. The conversation partner's overall switching behaviour had little impact on a bilingual's general switching rate, showing relatively low global alignment. However, local alignment was observed as switching was influenced by the partner's switching in the immediately preceding utterance. Together, these findings show that while production tasks without context can reliably measure switching costs, studying effects of context is necessary to better capture a bilingual's language-switching behavior.