Multilingual language control: evidence from N–2 language repetition costs

The n–2 language repetition cost has become a central marker in the study of multilingual language control, particularly as evidence for the persisting after-effects of reactive inhibition. This cost manifests when participants perform worse on trials requiring a return to a recently used language (ABA) compared to switching to a less recent one (CBA). While this pattern has traditionally been interpreted as a hallmark of inhibitory control in language production, its reliability, generalizability, and underlying mechanisms remain actively debated. This review synthesises findings from key studies employing the n–2 language repetition paradigm across both language production and comprehension. We examine experimental designs, including stimulus types (e.g. digits, pictures, words), task modalities (production vs. comprehension), participant populations (varying trilinguals), and analytic techniques (e.g. linear mixed-effects modelling, ERP measures). Robust n–2 language repetition costs have been consistently reported in production tasks, supporting the notion of persisting inhibition (e.g. Declerck, M., Thoma, A. M., Koch, I., & Philipp, A. M. (2015). Highly proficient bilinguals implement inhibition: Evidence from n-2 language repetition costs. Journal of Experimental Psychology: Learning, Memory, and Cognition, 41(6), 1911–1916; Philipp, A. M., Gade, M., & Koch, I. (2007). Inhibitory processes in language switching: Evidence from switching language-defined response sets. European Journal of Cognitive Psychology, 19(3), 395–416). However, emerging evidence from comprehension studies reveals more variable outcomes, including null effects and even repetition benefits (e.g. Liu, H., & Chaouch-Orozco, A. (2025). Language control in auditory bilingual comprehension: Uncovering novel evidence from the n − 2 repetition paradigm. Language and Cognition, 17, e15; Zhong, Z., Fan, L., Zhang, X., Jiang, J., & Yang, H. (2024). Inhibition processing in code-switching among Chinese–English–Japanese trilinguals: Evidence from the n–2 language repetition costs. International Journal of Bilingualism, 30(1), 18–34.). These discrepancies appear influenced by language dominance, modality, stimulus–response mappings, and interactional context. We argue that while the n–2 language repetition cost remains a valuable tool for probing inhibitory mechanisms, it should not be interpreted as a unitary index of language control. Instead, the effect reflects a complex interplay of control strategies, representational dynamics, and task demands. Future research should refine theoretical models to accommodate both inhibitory and non-inhibitory processes and systematically explore the boundaries of the n–2 language repetition costs in multilingual contexts.