Behavioral changes correlated with brain-stem auditory evoked responses in term infants with moderate hyperbilirubinemia

The purpose of this study was to test the hypotheses that newborn infants with moderate serum bilirubin concentrations have depressed Brazelton scores and increased brain-stem conduction time and that serum bilirubin levels correlate with Brazelton behavior scores and brain-stem auditory evoked response changes. Fifty term infants who were enrolled into either a low serum bilirubin group (less than 8 mg/dl) or a moderate serum bilirubin group (10 to 20 mg/dl) were tested with the Brazelton Neonatal Behavioral Assessment Scale and a brain-stem auditory evoked response test. Partial correlation analysis controlling for phototherapy revealed that increased bilirubin concentration correlated negatively with the Brazelton orientation and with state range clusters and individual Brazelton test items that involve auditory processing. Increased bilirubin concentration correlated with an increased latency of brain-stem auditory evoked response wave 4, 5. An increased interpeak 1-5 (brain-stem conduction time) correlated with the decreased animate visual and auditory item. We conclude that moderate hyperbilirubinemia in term infants affects both infant behavior, as measured by specific components of the Brazelton test, and brain-stem conduction time, as measured by the brain-stem auditory evoked response test.

Behavioral and psychophysiologic assessment of the preterm infant

Cardiorespiratory activity was recorded during attentional responsivity on the Brazelton scale in term and preterm infants. Preterm infants showed less heart rate deceleration, less heart rate variance and less power in the ECG spectrum at frequencies associated with respiratory sinus arrhythmia and oscillations in blood pressure: A lower threshold for attentional stimulation in the preterm infant may trigger a CNS mechanism that protects the infant from stimulus overload. Study of the coordination between behavioral and physiological reactivity provides an understanding of the role of the CNS in mediating information processing.

Effects of marijuana use during pregnancy on newborn cry

The effects of maternal marijuana use on the newborn cry were studied in Jamaica, where it was possible to rule out confounding factors such as the use of other substances and demographic variables that have clouded previous studies and where higher dosages may make the effects more visible. The acoustic characteristics of the cries of 20 infants of marijuana users and 20 controls were analyzed. The cries of the infants of marijuana users were shorter, had a higher percentage of dysphonation, a higher and more variable fundamental frequency, and a lower first formant than controls. There was also a dose response relation between the first formant and marijuana use. We suggest that heavy marijuana use affects the neurophysiological integrity of the infant.

Developmental outcome prediction from acoustic cry analysis in term and preterm infants

It has been suggested that the cry may reflect the neurophysiologic integrity of the infant and relate to later developmental outcome. In this study, the cry was recorded at term conceptional age in 18 preterm and 13 term infants using a standardized procedure and analyzed by high-speed computer. At 18 months of age, a significant number of infants were correctly classified as scoring high or low on the Bayley Scales of Infant Development based on the mean and variability in the fundamental frequency, variability in the first formant, and the amplitude of the cry. At 5 years of age, a significant number of infants were correctly classified on the McCarthy General Cognitive Index and on the verbal, perceptual-performance, and quantitative subscales based on the variability of the fundamental frequency, variability of the first formant, and amplitude and duration of the cry. Although preliminary, this study supports the potential use of the cry as a noninvasive measure to detect developmental outcome in the infant at risk.

Effects of atypical patterns of fetal growth on newborn (NBAS) behavior

Newborn infants who showed anthropometric signs of atypical patterns of fetal growth were compared with infants of appropriate growth on the Neonatal Behavioral Assessment Scale (NBAS) and on recently developed supplementary items. The sample consisted of lower-socioeconomic-status families in San Juan, Puerto Rico, and included teenage and older mothers. Infants with atypical patterns of fetal growth showed lower scores than did infants of appropriate growth on the NBAS orientation, motor, and reflex clusters and on 15 of the 18 supplementary scores. Gestational age was covaried and showed independent effects on 6 items. Differential effects on measures of state and autonomic function were also found when the effects of the ponderal index were held constant. The results suggested that neonatal behavior is related to multiple indices of fetal growth patterns that may indicate early versus late nutritional insult. Supplementary NBAS items do not improve the discriminability of the NBAS but may help explain the basis for observed group differences.

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.

Behavioral and cardiac rhythmicity during mother-father-stranger infant social interaction

In an effort to understand the temporal organization of infant physiologic and behavioral systems during social interaction with adults, spectral and cross-spectral analyses of infant heart rate and mother-father-stranger-infant behavioral data are described herein for a 3-month-old infant during face-to-face social interaction with her parents and a stranger. This infant's heart rate rhythms were stronger during social interaction with both mother and father than with a stranger. Infant behavioral rhythms were associated with (high coherence) the parents' behavioral rhythms, but not with those of the stranger. Furthermore, infant heart rate and infant behavioral rhythms showed high coherence with all three adults. Although these findings are preliminary, based on a case study and need replication, they generate intriguing hypotheses. This technique of studying the rhythmicity of infant social interaction with spectral analysis suggests that the 3-month-old infant's behavior and heart rate are synchronized during interaction with all three adults; however, the infant and adult behavioral rhythms are synchronous only with mother and father and not with an unfamiliar stranger.

Regional obstetric anesthesia and newborn behavior: a reanalysis toward synergistic effects

The Brazelton Neonatal Behavioral Assessment Scale was administered to 54 term, healthy infants on days 1, 2, 3, 4, 5, 7, and 10. Infants were divided into 8 groups of maternal obstetrical medication. A separate drug factor score was computed from 4 variables: time from (1) first and (2) last drug administration to delivery, (3) number of different drugs, and (4) drug administrations. In order to determine the additive effects of drug and other obstetric factors on neonatal behavior, the drug group and drug factor score plus length of labor, parity, and the ponderal index were used in a series of multiple regression analyses to predict Brazelton scale cluster scores on each day. In a second set of multiple regressions, these variables were used to predict the infant's rate of behavioral change as estimated by the slopes of the Brazelton scale cluster scores across the 7 days. The results indicated that the combined effect of the predictor variables significantly explained 10%-28% of the variance in neonatal behavior. It was hypothesized that the effects of low levels of medication are subtle but may be unmasked when medication effects are studied in combination with other factors that may potentiate drug effects.

Analysis of cry features in newborns with differential fetal growth

This article describes the relation between neonatal cry features and anthropometric indices of fetal growth. Ponderal indices were calculated to characterize 57 2-day-old infants as underweight for length, average weight for length, or overweight for length. Although no differences were found between the cry features of underweight and overweight infants, these infants at the extremes of the distribution of ponderal indices required more stimulation to elicit a pain cry and had a longer latency from the stimulus to cry onset and a higher fundamental frequency in the cry sound than infants with average ponderal indices. Whereas overweight infants cried for shorter amounts of time than average-weight infants, no differences were found in this sample between the underweight and average-weight infants. Test of differences in the variances of the groups paralleled the tests of mean differences. Because these cry features have been used to distinguish infants along a wide continuum of conditions where the functioning of an infant's central nervous system has been impaired or stressed, it was suggested that certain cry features may reflect the risk status of individual infants with anthropometric signs of both retarded and accelerated fetal growth.

Cultural and biomedical correlates of neonatal behavior

The Brazelton Neonatal Behavioral Assessment Scale was administered to 24 each Puerto Rican, Black, and Caucasian, 2-day-old, full-term healthy neonates. Comparisons on 8 Brazelton scale summary scores showed that Puerto Rican infants scored lower on habituation, higher on orientation, and higher on maintaining their organization with increasing stimulation than Black and Caucasian infants. Multiple regression analysis showed that the combination of biomedical variables was significantly correlated with 6 of the Brazelton scale summary scores for the Puerto Rican infants, 1 summary score for the Caucasian infants, and none for the Black infants; it revealed population differences with respect to the synergistic effects of biomedical variables on neonatal behavior.

A comparative study of the behavior of Greek neonates

Three groups of 30 Greek neonates each (an adoptive group from the Metera orphanage, a lower-class group, and a middle-class group) were evaluated at days 1, 5, and 10 after birth using a behavioral scale of 21 items and a neurologic evaluation of 16 items. Behaviors were examined for group differences and group-by-age recovery curves were determined during the first ten days. Significant differences were found in the separate items and items grouped to reflect interactive, motor, and state behavioral dimensions. The adoptive babies at the Metera orphanage generally performed the most poorly. This difference seems not only to reflect intrauterine differences, especially in regard to nutrition, but to point to the likelihood of eliciting less than optimal responses from future environments. The middle-class group had the worst scores on physiologic items and were similar to the Metera babies in having initially depressed interactive, motor, and state behavior. Improvement in these areas over ten days suggested that temporary effects of maternal medication caused the poor scores. The recovery curves of the infants pointed to the important effects of such perinatal variables as maternal medication on early neonatal behavior.