Native language shifts across sleep-wake states in bilingual sleeptalkers

Study Objectives: To assess language used during episodes of sleeptalking i n bilingual children. Design: The investigation was accomplished through the parents who, after h aving received appropriate information, participated by filling out a surve y on sleeptalking. Settings: The study was performed in three bilingual schools of the Basque country, a region in northern Spain in which two completely different offic ial languages are spoken. Patients: A total of 1000 parents agreed to participate, and 681 children w ere studied. Measurements and Results: Sleeptalking was reported by 383 (56.3%) of child ren (mean age 9 years; range: 3-17). Most individuals used their dominant ( ie, native) language during sleep. However, a minority (<4%) were found to use their nondominant language persistently during episodes of sleeptalking . Conclusions: Balanced bilinguals (those who have equal proficiency in both languages) may sleeptalk in either of the two languages. Dominant bilingual s (ie, having greater proficiency in one language) may preferentially sleep talk in their dominant language, with immediate past events probably influe ncing language use in individual subjects on particular nights. Several con siderations are postulated as an explanation for the group who systematical ly exhibited a dominance shift during sleep.