Prenatal cigarette exposure and infant learning stimulation as predictors of cognitive control in childhood.

Prenatal exposures to neurotoxins and postnatal parenting practices have been shown to independently predict variations in the cognitive development and emotional-behavioral well-being of infants and children. We examined the independent contributions of prenatal cigarette exposure and infant learning stimulation, as well as their inter-relationships in predicting variations in the proficiency of executive attention, a core element of cognitive control and self-regulation. Participants were an ethnic-racially, socio-economically diverse sample of 249 children followed from birth in the Project on Human Development in Chicago Neighborhoods. We obtained histories of prenatal exposure to alcohol, cigarettes, and other drugs, and we assessed socio-economic status and learning stimulation during a home visit when the participants were infants. In childhood we utilized the Attention Networks Test to assess the proficiency of executive attention during two home visits, one year apart. Accounting for age, SES, prenatal alcohol exposure, and baseline performance, we found that prenatal cigarette exposure impaired the speed of executive attention. Infant learning stimulation mitigated these effects, and predicted better accuracy of executive attention as well, suggestive of both protective and health promoting effects. Effect sizes for these relations, whether examined independently or by their inter-relationships, were comparable to if not greater in magnitude than the effects of age on speed and accuracy, highlighting the importance of these very early experiences in shaping the proficiency of self-regulation. Since executive attention is central to cognitive control and self-regulation, previously described relations between prenatal cigarette exposure, parenting practices, and some forms of childhood psychopathology may be contingent on how early learning stimulation contributes to the proficiency of executive attention through direct and indirect effects. Furthermore, considering the prolonged developmental trajectory of executive attention, interventions to support provision of learning stimulation may mitigate poor outcomes for some at-risk children by promoting development of more proficient executive attention.