The Effects of Bilingualism and Vocabulary Size on Infants’ Cognitive Control

Sadaf Pour Iliaei
There is increasing evidence that bilingualism may lead to cognitive advantages, and some evidence suggests that these may emerge as early as infancy. The present study examined if such advantages could be found in preverbal bilingual infants (7-month-olds), and older bilingual infants who have an emerging vocabulary (20-month-olds). We compared monolinguals and bilinguals in an anticipatory eye movement paradigm. During the training phase, infants learned to use a visual and auditory cue to anticipate a visual reward on one side of a screen. During the test phase, the reward would appear on the opposite side of the screen, necessitating infants to inhibit the previously-learned rule. Results suggest that both 7-month-old and 20-month-old bilingual infants were better able to inhibit their previously learned response than monolinguals. This effect was most apparent in the middle block of test trials. At 20 months, infants with lower vocabulary size were more engaged in the task, showing more total anticipations (both correct and incorrect) than those with higher vocabulary size. Overall, this research provides some evidence that bilingualism may lead to improvements in cognitive control for preverbal and older infants.
Keywords: infancy, bilingualism, cognitive control, inhibitory control, eye-tracking