Effects of fetal alcohol exposure on infant reaction time.

Fetal alcohol exposure is associated with slower reaction times (RTs) in children, suggesting an alcohol-related deficit in "speed of central processing." This study examined effects of prenatal alcohol exposure on a new paradigm which, for the first time, directly assesses RT in infancy. RT was assessed in 103 Black, inner-city, 6.5-month-olds born to women recruited prenatally based on alcohol consumption during pregnancy. Maternal drinking was related to longer RTs and to fewer fast responses, after controlling for potential confounders. The incidence of fast performance was reduced in infants whose mothers averaged at least 0.5 oz absolute alcohol/day, indicating an impact at lower levels than those associated with fetal alcohol syndrome. The RT deficits were dose-dependent and not attributable to maternal depression, intellectual stimulation, prenatal drug exposure, or postpartum maternal drinking. This study provides the first evidence of an alcohol-related RT deficit in infancy.