Abstract
Speech perception consistency refers to the similarity between a listener’s responses to repeated presentations of the same speech sound (e.g., along a /ba/–/pa/ continuum). Although research has demonstrated multiple advantages of consistency, its role in initial lexical activation (i.e., early activation of word candidates) and speech perception flexibility (e.g., the ability to recover from misleading speech input) has not been tested. We investigated the role of consistency in spoken-word recognition among Spanish (L1)–English (L2) bilingual listeners. Focusing on the bilabial stop contrast (/b/–/p/), consistency was measured in a task where participants repeatedly rated speech sounds on a continuous scale (Visual Analog Scale), whereas initial lexical activation and speech perception flexibility were assessed using a word-to-picture matching task with eye-tracking (Visual World Paradigm). Seventy Spanish–English bilinguals completed these tasks in both languages. Listeners with higher consistency exhibited stronger initial lexical activation for acoustically compatible word candidates across /b/ and /p/ in L1 Spanish and for /p/ in L2 English. However, consistency was not associated with speech perception flexibility. These findings suggest that speech perception consistency primarily supports early lexical activation during spoken-word recognition, while playing a more limited role in later processes involved in revising initial misinterpretations.
Data availability
The datasets generated during and/or analyzed during the current study are available in the OSF repository, [https://doi.org/10.17605/OSF.IO/QXMYK](https:/doi.org/10.17605/OSF.IO/QXMYK).
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Acknowledgements
We would like to acknowledge Amets Esnal and Itziar Basterra for organizing the data collection, Ainhoa Eguiguren for the translations of the task instructions, and Daphne Weiss and Elena Alguirrebengoa for recording the stimuli for the present study. We would also like to thank Hyoju Kim and an anonymous reviewer for their constructive comments on a previous version of the manuscript.
Funding
This research is supported by the Basque Government through the BERC 2022–2025 program and funded by the Spanish State Research Agency through BCBL Severo Ochoa excellence accreditation CEX2020-001010/AEI/https://doi.org/10.13039/501100011033. This research was supported by a predoctoral fellowship (grant PRE2021-097223, associated with project CEX2020-001010-S–21–2) funded by the Spanish Ministry of Science and Innovation (MCIN), the State Research Agency (AEI), and the European Social Fund Plus (FSE+), awarded to Brian W. L. Wong. Support for this project was provided by the Spanish Ministry of Science and Innovation through Grant # PID2020-113348GB-I00 and # PID2023-146423NB-I00, awarded to Arthur Samuel and Efthymia Kapnoula. This work was supported by the Ramón y Cajal Program, funded by MCIN/AEI/https://doi.org/10.13039/501100011033 and by the ESF+, under Grant # RYC2022-035505-I, awarded to Efthymia Kapnoula.
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Conceptualization: Brian W. L. Wong, Arthur G. Samuel, Efthymia C. Kapnoula; Methodology: B. W. L. W., A. G. S., E. C. K.; Investigation: B. W. L. W.; Software: B. W. L. W., E. C. K; Formal analysis: B. W. L. W., E. C. K; Writing - original draft preparation: B. W. L. W.; Writing - review and editing: B. W. L. W., A. G. S., E. C. K; Supervision: E. C. K, A. G. S.
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Wong, B.W.L., Samuel, A.G. & Kapnoula, E.C. Speech perception consistency facilitates initial lexical activation, but not speech perception flexibility. Sci Rep (2026). https://doi.org/10.1038/s41598-026-47943-3
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DOI: https://doi.org/10.1038/s41598-026-47943-3
