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The effects of fetal cocaine exposure on newborn cry characteristics were studied in 80 cocaine-exposed and 80 control infants. The groups were stratified to be similar on maternal demographic characteristics and maternal use of other illegal substances and alcohol during pregnancy. The hypothesis was that excitable cry characteristics were related to the direct effects of cocaine, while depressed cry characteristics were related to the indirect effects of cocaine secondary to low birthweight. Structural equation modeling (EQS) showed direct effects of cocaine on cries with a longer duration, higher fundamental frequency, and a higher and more variable first formant frequency. Indirect effects of cocaine secondary to low birthweight resulted in cries with a longer latency, fewer utterances, lower amplitude, and more dysphonation. Cocaine-exposed infants had a lower birthweight, shorter length, and smaller head circumference than the unexposed controls. Findings were consistent with the notion that 2 neurobehavioral syndromes, excitable and depressed, can be described in cocaine-exposed infants, and that these 2 syndromes are due, respectively, to direct neurotoxic effects and indirect effects secondary to intrauterine growth retardation.

The Brazelton Neonatal Assessment Scale was administered to 52 newborn infants. A factor analysis revealed 2 main factors, 1 along an attention-orientation dimension, the other relating to temperament arousal. A stepwise multiple linear regression analysis showed that the attention-orientation factor was related to birth weight, age of the mother, and sex and race of the baby. The only variable related to the temperament-arousal factor was 5-min Apgar scor. The study, although exploratory, demonstrates the use of multivariate techniques in the assessment of influences on newborn behavior.

This article describes 2 experiments which examine the relation between neonatal cry features and obstetric histories. Experiment 1 shows that 24 clinically healthy, normal newborns who may be at risk due to a high number of prenatal and perinatal complications can be distinguished from 24 low-complications infants by harmonic and durational features of the cry. High-complications infants required more stimulation to elicit the cry, had a longer latency to cry onset, a shorter first cry expiration, a higher cry pitch, and cried less in total time than low-complications infants. In experiment 2, naive adults rated the high-complications infant cries as more aversive, grating sick, urgent, distressing, piercing, discomforting, and arousing than low-complications infant crues. Factor analyses showed that although the low-complications infant cries were described along one dimension of discomfort, a second factor emerged conveying the "sick" nature of the sound of the cry of the high-complications infants. It was suggested that certain cry features may reflect the risk status of the infant.

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.