Putting new words to sleep: Novel word learning depends on individual differences in bilingual experience

Abstract We investigated how bilingual adults lexicalized novel words ( bloksom ) derived from existing English words ( blossom ), over a 24-h interval that included sleep, as a function of word-related factors (lexical frequency), task-related factors (inferencing during encoding), and individual differences in compartmentalized versus integrated bilingual use (language entropy). In Experiment 1, 48 bilingual adults explicitly learned novel word–picture pairings. In Experiment 2, 50 bilingual adults implicitly learned the same pairings. Both experiments manipulated task conditions to require an inference (Inference +) versus absence of inference (Inference −). Participant performance was responsive to word-related factors (word frequency). However, participants who use multiple languages in a low-entropy, compartmentalized manner were most responsive to explicitly tuned task factors. In contrast, participants who use their languages in a high entropy, integrated manner were most responsive to implicitly tuned task factors. These data suggest that bilingual experience modulates preferred novel word learning styles in adult bilinguals.