Effects of bilingualism on statistical learning in preschoolers

Earlier work indicates that bilingualism may positively affect statistical learning, but leaves open whether a bilingual benefit is (1) found during learning rather than in a post-hoc test following a learning phase and (2) explained by enhanced verbal short-term memory skill in the bilinguals. Forty-one bilingual and 56 monolingual preschoolers completed a serial reaction time task and a nonword repetition task (NWR). Linear mixed-effect regressions indicated that the bilinguals showed a stronger decrease in reaction times over the regular blocks of the task than the monolinguals. No group differences in accuracy-based measures were found. NWR performance, which did not differ between the groups, did not account for the attested effect of bilingualism. These results provide partial support for effects of bilingualism on statistical learning, which appear during learning and are not due to enhanced verbal short-term memory. Taken together, these findings add to a growing body of research on effects of bilingualism on statistical learning, and constitute a first step towards investigating the factors which may underlie such effects.