Cognitive correlates of infant attention and maternal stimulation over the first year of life.

This study investigated the predictability of cognitive differences at 12 months from infant and maternal behaviors at 4 months. Babies who showed more habituation and faster habituation at 4 months scored higher on the Bayley Scales and had larger speaking vocabularies at 12 months. Success with select 4-month Bayley Scale items also predicted 12-month Bayley scores but did not predict speaking vocabulary. Additionally, 4-month-olds who vocalized more or who more frequently manipulated objects spoke more words at 12 months and als tended to score higher on the Bayley Scales at 12 months. Frequent maternal stimulation at 4 months, specifically, by encouraging babies' attention to objects, correlated with the size of speaking vocabulary at 12 months; a cross-lagged panel correlation suggested that maternal stimulation positively influenced infants' cognitive development. Regression analyses examined the power of combinations of infant and maternal predictors. Overall, the results show that some individual differences in cognition may be predictable across the first year of life.