Dataset for: Investigating Inhibition in German-Turkish Multilinguals: The Role of Language Dominance and Language Context in Bilingual and Trilingual Language Switching

Language production in multilinguals typically involves the simultaneous activation of multiple languages, leading to interference. The Inhibitory Control Model (ICM) posits that this interference is resolved through the inhibition of non-target languages, yet evidence of inhibition markers during language switching is often ambiguous. This study tested 24 balanced German-Turkish multilinguals (L1a German, L1b Turkish, L2 English) in cued picture naming and assessed n-2 language repetition costs as a marker of inhibition. These costs reflect persisting inhibition when switching back to a previously abandoned language (e.g., German-English-German) relative to a control condition (e.g., Turkish-English-German). We also asked participants to switch in all three pairwise language combinations in separate blocks, before and after the switching block with all three languages, to assess n-1 switch costs as a function of language pairing. Overall, we found n-2 language repetition costs, but these costs were not significantly stronger for the more dominant language(s). Moreover, all pairwise n-1 switch costs were symmetric, showing no evidence for differential control as a function of language dominance. Finally, we found that the intense switching experience with three languages produced a sustained relative downregulation of L1a German, suggesting proactive control of L1a German. Together, these findings provide support for inhibition being the main underlying mechanism of language control and question how language dominance relates to the strength of language control.