Reactivity and regulation in cocaine-exposed neonates

This study examined behavioral and physiologic regulation in 14 full-term neonates who were exposed to cocaine antenatally. A group of 14 non-cocaine-exposed infants served as controls. Data on behavioral state, cardiac patterning (heart period and vagal tone), and habituation to a standardized stimulus were collected. There were no differences between cocaine-exposed and nonexposed infants in heart period or vagal tone during an undisturbed period. There were significant differences in behavioral state regulation: Cocaine-exposed infants displayed significantly greater state lability and shorter sleep bouts, fussed or cried more often, and spent less time asleep and more time in transitional states. Both groups responded to an auditory stimulus with shorter heart period, but cocaine-exposed neonates demonstrated a larger response. In addition, cocaine-exposed neonates displayed less behavioral response decrement to repeated presentations of the stimulus. Although there are limitations to attribution of these results to cocaine alone, the results are discussed in relation to prevailing clinical impressions of cocaine-exposed neonates.