Abstract Earlier studies showed that bilinguals exhibit higher metacognitive efficiency than monolinguals. However, bilinguals do not represent a homogeneous population, and we don't know which aspects of bilingualism lead to metacognitive advantage. We studied if the language used as a medium of education might affect metacognition. Participants were asked to evaluate how certain they are when they make decisions, and good metacognition—ability to evaluate one's own decision—is manifested in lower confidence ratings assigned to wrong decisions (i.e., correctly detecting those cases when the probability of error is increased, and adapting confidence ratings accordingly). We measured metacognition in Frisian‐German ( N = 24) and Danish‐German bilinguals who either used ( N = 39) or didn't use ( N = 23) a minority language in formal education, in three language tasks: syntactic (artificial grammar learning), semantic (inferential word learning) and speech segmentation (statistical learning). We found that using a minority language in multilingual areas or a second language (in the order of acquisition) may promote metacognitive efficiency in bilinguals. Bilingual advantage in metacognition relies on the need to monitor different language processing cognitive strategies rather than on the need to monitor who said what to whom in which language and why. As metacognition is associated with academic achievements, it might be worthwhile to consider this finding in bilingual schools when developing language policy in bilingual areas and probably alternate languages so that all students can benefit from immersion in a bilingual education. Context and implications Rationale for this study : Earlier studies showed that bilinguals exhibit higher metacognitive efficiency than monolinguals. However, bilinguals do not represent a homogeneous population, and it is not yet clear which aspects of bilingualism lead to metacognitive advantage. Here, we showed that one of the bilingualism‐related factors that contributes to enhanced metacognition in bilinguals is related to which language is used as a medium of education (at least in high school). Why the new findings matter : Many bilingual schools follow the principle of one subject–one language throughout all academic years and do not alternate the language in which a particular subject is taught from year to year. We should be aware of advantages but also of disadvantages of this policy in the context of bilingual education. Implications for policy makers in bilingual education and researchers : Using a minority language in multilingual areas or a second language (in the order of acquisition) is one of the factors that may promote metacognitive efficiency in bilinguals, given that they have sufficient language proficiency to use the language for educational purposes. As metacognition is associated with academic achievements, it might be worthwhile to consider this finding in bilingual schools when developing language policy in bilingual areas and probably alternate languages so that all students can benefit from immersion in a bilingual environment. Researchers should be aware that different dimensions of bilingualism differentially influence metacognition.
Ordin et al. (Fri,) studied this question.