Effect of dual-language exposure in infancy on language and cognition: Evidence from a South-Indian birth cohort

Background: Language and cognitive development in infancy is a complex process with multifactorial influences. The effort made by the infant to attain language development can improve cognition. From the longitudinal followup of a birth cohort, we explore the relationship of dual language exposure on cognition and language development at two years of age.Methods: For this study, 251 children from a low-middle-income urban population in Vellore were recruited at birth as part of a multi-national multidisciplinary study and followed up at serial intervals as per the original study protocol. Languages spoken include Tamil, Urdu and Telugu and data about language exposure were collected. BayleyScales of Infant Development was used to assess cognition and language development at two years of age.Results: Out of 228 children who were recruited at two years of age, 169 (74.1%) children were monolinguals and 59 (25.9%) bilinguals. The average composite scores (SD) for cognition and language components were 93.3 (7.5) and 99.1 (9.4) respectively. At two years of age, both language and cognitive development was comparable for both monolinguals and bilinguals, adjusting for sex, socioeconomic status and maternal education.Conclusion: There was no significant effect of early dual language exposure on language and cognition at two years of age in an urban low-middle-income community setting in South India.