The threshold hypothesis is a hypothesis concerning second language acquisition set forth in a study by Jim Cummins (1976),Cummins J. (1976). The influence of bilingualism on cognitive growth: a synthesis of research findings and explanatory hypotheses. Work. Pap. Biling. 9, 1–43 which states that a minimum threshold in language proficiency must be reached in both languages before a second-language speaker can reap the cognitive benefits of being bilingual. It also states that, in order to gain proficiency in a second language, the learner must also have passed a certain and age appropriate level of competence in his or her first language.
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