Barry M. Lester

Theory and research in behavioral pediatrics

Eight contributions address: material cocaine use and neonatal outcome; nonorganic failure to thrive; understanding and controlling violence; the role of school in prosocial development; lateralization of function; lateralized behavior organization during infancy; parent-infant interaction; and manu

The Rhythmic Structure of Mother-Infant Interaction in Term and Preterm Infants.

The purpose of this study was to quantify social interaction rhythms in 3- and 5-month-old term and preterm infants and their mothers. Infant-mother dyads were videotaped in a 3-min face-to-face paradigm. For each second of the interaction, separate scores were assigned to infant and mother indicating levels of affective involvement, creating 2 180-sec time series. Spectral and cross-spectral techniques were used to quantify periodicities in each member of the dyad and to estimate the synchrony or coherence of interactional rhythms between each infant and mother. Results showed the existence of periodicities in the behavior of each infant and mother at 3 and 5 months, with most subjects showing spectral peaks between .022 and .10 Hz. Increases from 3 to 5 months in behavioral periodicities were found for infants and mothers as well as for the coherence between infant-mother dyads. Term dyads showed higher coherence than preterm dyads at both 3 and 5 months. Term infants more often led the interaction at both ages. These results were taken as evidence that behavioral periodicities, which may be biologically based, underlie early mother-infant interaction and provide a temporal structure for the organization of cognitive and affective experience. Differences in synchrony between term and preterm infants may explain later reported differences in language between these groups.

The Infant Development, Environment, and Lifestyle Study: Effects of Prenatal Methamphetamine Exposure, Polydrug Exposure, and Poverty on Intrauterine Growth

OBJECTIVE. Methamphetamine use among pregnant women is an increasing problem in the United States. Effects of methamphetamine use during pregnancy on fetal growth have not been reported in large, prospective studies. We examined the neonatal growth effects of prenatal methamphetamine exposure in the multicenter, longitudinal Infant Development, Environment and Lifestyle study. DESIGN/METHOD. The Infant Development, Environment and Lifestyle study screened 13808 subjects at 4 clinical centers: 1618 were eligible and consented, among which 84 were methamphetamine exposed, and 1534 were unexposed. Those who were methamphetamine exposed were identified by self-report and/or gas chromatography-mass spectrometry confirmation of amphetamine and metabolites in infant meconium. Those who were unexposed denied amphetamine use and had a negative meconium screen. Both groups included prenatal alcohol, tobacco, or marijuana use, but excluded use of opiates, LSD, PCP or cocaine only. Neonatal parameters included birth weight and gestational age in weeks. One-way analysis of variance and linear-regression analyses were conducted on birth weight by exposure. The relationship of methamphetamine exposure and the incidence of small for gestational age was analyzed using multivariate logistic-regression analyses. RESULTS. The methamphetamine exposed group was 3.5 times more likely to be small for gestational age than the unexposed group. Mothers who used tobacco during pregnancy were nearly 2 times more likely to have small-for-gestational-age infants. In addition, less maternal weight gain during pregnancy was more likely to result in a small-for-gestational-age infant. Birthweight in the methamphetamine exposed group was lower than the unexposed group. CONCLUSIONS. These findings suggest that prenatal methamphetamine use is associated with fetal growth restriction after adjusting for covariates. Continued follow-up will determine if these infants are at increased risk for growth abnormalities in the future.

Orientation to social and nonsocial stimuli in neonatal chimpanzees and humans

Abstract The behavioral capabilities of neonatal chimpanzees are not well known. A major goal of this study was to document their ability to orient to social and nonsocial objects and to compare their performance with that of human infants. The Brazelton Neonatal Behavioral Assessment Scale (NBAS) was administered to 13 nursery-reared chimpanzees, every other day during their first month of life, and to 42 humans, twice, on the third and thirtieth day of life. The orientation items included social stimuli (a human face and both human and chimpanzee sounds) and nonsocial stimuli (a red ball and a red rattle). Repeated-measures analysis of variance on the orientation cluster of the NBAS revealed that chimpanzee neonates have the capacity for sustained attention to all stimuli, both social and nonsocial, indistinguishable from that of human neonotes. Significant improvements in orientation performance from Day 2 to Day 30 were found for both species. These striking similarities in early orientation ability are viewed as a challenge to notions of unique human propensities.

Methamphetamine and Other Substance Use During Pregnancy: Preliminary Estimates From the Infant Development, Environment, and Lifestyle (IDEAL) Study

Objectives: Methamphetamine use is a continuing problem in several regions of the United States and yet few studies have focused on prenatal methamphetamine exposure. The purpose of this study was to estimate the prevalence and correlates of alcohol, tobacco, and other substance use—including methamphetamine—during pregnancy. Methods: The sample consisted of the first 1632 eligible mothers who consented to participate in a large-scale multisite study focused on prenatal methamphetamine exposure. This unselected screening sample included both users and nonusers of alcohol, tobacco, methamphetamine, and other drugs. Substance use was determined by maternal self-report and/or GC/MS confirmation of a positive meconium screen. Results: Overall, 5.2% of women used methamphetamine at some point during their pregnancy. One quarter of the sample smoked tobacco, 22.8% drank alcohol, 6.0% used marijuana, and 1.3% used barbiturates prenatally. Less than 1% of the sample used heroin, benzodiazapenes, and hallucinogens. Multivariate modeling results showed that tobacco smokers and illicit drug users were more likely to be single and less educated, have attended less than 11 prenatal visits, and utilize public financial assistance. Conclusions: This is the first large-scale investigation to report the prevalence of methamphetamine use during pregnancy in areas of the United States where methamphetamine is a notable concern. Follow-up research is ongoing to investigate the outcomes associated with prenatal methamphetamine exposure. Given that this research extends and confirms previous findings showing that high-risk groups of pregnant women can be identified on the basis of basic demographic characteristics, targeted interventions are greatly needed to reduce serious adverse outcomes associated with prenatal alcohol and tobacco use.

Possible association between fluoxetine hydrochloride and colic in an infant

This is a case study of a 6-week-old infant referred for colic whose mother was using fluoxetine hydrochloride and breast feeding the infant. The mother switched to a commercial formula and reported a dramatic decrease in the infants crying. We asked the mother to feed the infant breast milk from a bottle and she agreed. Throughout the study the mother kept a daily diary of her infants crying, sleeping, stooling patterns, and feeding problems. Analysis of the mothers breast milk showed concentrations of 69 ng/mL for fluoxetine and 90 ng/mL for norfluoxetine. Infant blood serum/plasma level was analyzed for fluoxetine hydrochloride following return to breast milk. The concentrations were 340 ng/mL for fluoxetine and 208 ng/mL for norfluoxetine. The diary records showed increased crying, decreased sleep, increased vomiting, and watery stools when fluoxetine hydrochloride was transmitted through breast feeding or breast milk in bottle. These symptoms were reduced when the infant was formula fed. We suggest a possible relationship between colic and associated symptoms and fluoxetine hydrochloride in maternal breast milk.

Low birth weight and preterm births: Etiologic fraction attributable to prenatal drug exposure

OBJECTIVES:To determine the factors that would increase the likelihood of outcomes: low birth weight (LBW), preterm births and intrauterine growth restriction (IUGR).STUDY DESIGN:Secondary data analysis from a multi-center study. Risk factors for each outcome were derived from logistic regression models. Odds ratios (OR), 95% confidence intervals, and population-attributable risk proportions (PAR%) were estimated.RESULTS:Prenatal cocaine exposure increased the likelihood of LBW (OR: 3.59), prematurity (OR: 1.25), and IUGR (OR: 2.24). Tobacco, but not marijuana, significantly influenced these outcomes. Alcohol had an effect on LBW and IUGR. Etiologic fractions (PAR%) attributable to tobacco for LBW, prematurity, and IUGR were 5.57, 3.66, and 13.79%, respectively. With additional drug exposure including cocaine, estimated summary PAR% increased to 7.20% (LBW), 5.68% (prematurity), and 17.96% (IUGR).CONCLUSION:Disease burden for each outcome increases with each added drug exposure; however, etiologic fraction attributable to tobacco is greater than for cocaine.

The roles of DNA methylation of NR3C1 and 11β-HSD2 and exposure to maternal mood disorder in utero on newborn neurobehavior

Exposure to maternal mood disorder in utero may program infant neurobehavior via DNA methylation of the glucocorticoid receptor (NR3C1) and 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD-2), two placental genes that have been implicated in perturbations of the hypothalamic pituitary adrenocortical (HPA) axis. We tested the relations among prenatal exposure to maternal depression or anxiety, methylation of exon 1F of NR3C1 and 11β-HSD-2, and newborn neurobehavior. Controlling for relevant covariates, infants whose mothers reported depression during pregnancy and showed greater methylation of placental NR3C1 CpG2 had poorer self-regulation, more hypotonia, and more lethargy than infants whose mothers did not report depression. On the other hand, infants whose mothers reported anxiety during pregnancy and showed greater methylation of placental 11β-HSD-2 CpG4 were more hypotonic compared with infants of mothers who did not report anxiety during pregnancy. Our results support the fetal programming hypothesis and suggest that fetal adjustments to cues from the intrauterine environment, in this case an environment that could be characterized by increased exposure to maternal cortisol, may lead to poor neurodevelopmental outcomes.

The Brazelton Neonatal Behavioral Assessment Scale (BNBAS)

SummaryThe Brazelton Neonatal Behavioral Assessment attempts to capture the behaviors of the neonate as he defends himself from intrusive, negative stimuli, and controls interfering motor and autonomic responses in order to attend to important social and nonsocial stimuli. In order to conceptualize the 26 behavioral items and 20 reflex scores, four clusters or typologies have been identified which help to reduce the data for analytic purposes with small numbers of subjects. So far few long-term validation studies have been completed, although the scale is in use in many different areas, such as obstetrical medication, predicting to neurological deficits, cross-cultural differences, and with low birth weight infants.

Impact of prenatal cocaine exposure on child behavior problems through school age.

OBJECTIVE. We examined the trajectory of childhood behavior problems after prenatal cocaine exposure. METHODS. The Maternal Lifestyle Study, a longitudinal cohort study, enrolled children between 1993 and 1995 at 4 centers. Prenatal cocaine exposure was determined from mothers who admitted use and/or meconium results. Exposed children were matched with a group of nonexposed children within site and by gestational age, gender, race, and ethnicity. The study began at the 1-month corrected age with a total of 1388 children enrolled. A total of 1056 were assessed for internalizing, externalizing, and total behavior problems at ages 3, 5, and 7 years using the Child Behavior Checklist. Longitudinal hierarchical linear models were used to determine the effect of prenatal cocaine exposure on behavior problem trajectories while controlling for other prenatal exposures; time-varying covariates, including ongoing caregiver use of legal and illegal substances; demographic factors; family violence; and caregiver psychological distress. RESULTS. High prenatal cocaine exposure was associated with the trajectory of internalizing, externalizing, and total behavior problems; these effects were independent of and less than the significant combined effect of prenatal and postnatal tobacco and alcohol exposures. Caregiver depression and family violence had independent negative influence on all behavior outcomes. CONCLUSIONS. Prenatal cocaine exposure has a negative impact on the trajectories of childhood behavior outcomes. When they co-occur with prenatal cocaine exposure, prenatal and postnatal tobacco and alcohol exposures have added negative effects on behavior outcomes.