Bilingual flexibility: How everyday fluctuations in language environment shape short-term language control and long-term language adaptation

• Applicant: Professor Dr. Andreas Neubauer
• Subject Area: General, Cognitive and Mathematical Psychology ; Developmental and Educational Psychology ; Personality Psychology, Clinical and Medical Psychology, Methodology
• Term: since 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 548577702

Bilingual individuals – broadly defined as individuals who regularly speak at least two languages – are able to flexibly switch between multiple languages. Bilingual flexibility allows these individuals to adapt their language use to current task- and situation-specific linguistic and social demands. Previous research has targeted this language control process primarily using laboratory-based experimental studies which allow for a better understanding of language control in controlled settings. So far, it remains unclear, to what extent the processes identified in laboratory settings generalize to experiences in bilingual individuals’ everyday lives. The present project examines to what extent current situational demands in bilinguals’ everyday lives (specifically, short-term and long-term changes in the language environment which surround bilinguals in their daily lives) modulate their ability to switch between languages. A test battery capturing both momentary language environment and momentary language proficiency will be developed in this project and used to examine the links between these two constructs in the daily lives of German-English bilinguals. Using ambulatory assessment, this project will explore the dynamic within-person association between language environment and language proficiency in natural contexts. Furthermore, the project will examine the effects of longer-lasting changes in the language environment on bilingual flexibility. Specifically, using a longitudinal measurement burst study the present research will examine changes in the levels and associations of language environment and language proficiency in a sample of university students from before to during studying abroad. By bringing together ambulatory assessment methods and longitudinal measurement burst designs with established experimental paradigms to examine language switching, the present research will illuminate how changes in bilingual individuals’ language environment are related to bilingual flexibility on multiple time scales – from moment-to-moment fluctuations to changes across several months.

• DFG Programme: Research Units
• Subproject of: FOR 5905: Bilingual Flexibility – The Psychology of Language Control