Examining non-task language effect on production-based language switching: Evidence from Tibetan-Chinese-English trilinguals.

This article investigates the non-task language effect in production-based language switching among Tibetan-Chinese-English trilingual 11th-grade students. Across three experiments, each involving a different non-task language (one of the trilinguals' languages not used in the switching task), participants with comparable proficiency in the two task languages but differing proficiency in the non-task language performed picture naming tasks. Analyses of response times and error rates revealed no significant influence of non-task language proficiency on language switching performance, suggesting a null non-task language effect. The authors propose that trilinguals employ proactive language control mechanisms to manage interference from non-task languages, differing from the inhibitory control applied to non-target languages. These findings contribute to understanding trilingual language control by indicating that non-task languages may be continuously suppressed without incurring additional switching costs during production-based language switching.