Vagal Reactivity and Affective Adjustment in Infants during Interaction Challenges

Respiratory sinus arrhythmia (RSA) and heart period were evaluated in 5-month-old infants (N = 40) during interaction challenges requiring affective adjustment. The paradigm consisted of four 2-min experimental conditions designed to elicit behavioral and autonomic responses to object-mediated (Picture Attention and Toy Attention) and person-mediated (Still Face and Social Interaction) engagement. The data demonstrated that autonomic state systematically changed during engagement and disengagement with the environment. During the object-mediated challenge, increases in RSA were uniquely related to positive engagement. During the person-mediated challenge, there was a more complex integration of autonomic and behavioral responses characterized by concordant increases and decreases in RSA, heart period, positive engagement, negative affect, and motor activity. When participants were partitioned into two groups, based on their RSA response pattern during the person-mediated challenge, only participants who exhibited a pattern of RSA decrease from Toy Attention to Still Face followed by a rapid recovery during Social Interaction demonstrated regulation of behavioral activity, including concordant recovery from stress. These findings provide additional empirical support for the role of vagal regulation of the heart in the modulation of affective adjustment and engagement behavior.     

Relationship of Apgar scores and Bayley mental and motor scores.

Infants with 0-3 Apgar scores at 1 minute had significantly lower 8-month mental and motor scores than infants with 7-10 scores and significantly lower mental but not motor scores than infants with 4-6 Apgar scores. Correlations indicated significant relationships (independent of birth weight) between Apgar scores and Bayley mental and motor scores for random, Colored Portuguese, and total samples but not for Negroes and whites. Results demonstrated a significant difference in Apgar scores by 8-month classifications with significantly lower scores for children classified as abnormal, and by longevity with significantly lower scores for neonates who died within 2 days.     

Cardiac vagal regulation and early peer status

A sample of 341 5 (1/2) -year-old children participating in an ongoing longitudinal study was the focus of a study on the relation between cardiac vagal regulation and peer status. To assess cardiac vagal regulation, resting measures of respiratory sinus arrhythmia (RSA) and RSA change (suppression) to 3 cognitively and emotionally challenging tasks were derived. Results indicated that vagal regulation was positively associated with peer status. In addition, mediational analyses revealed that the relation between vagal regulation and peer status was mediated through better social skills for girls and better social skills and fewer behavior problems for boys. These findings are discussed in terms of the role of vagal regulation in the facilitation of children's positive social behavior.     

Prenatal Antecedents of Newborn Neurological Maturation

Fetal neurobehavioral development was modeled longitudinally using data collected at weekly intervals from 24 to 38 weeks gestation in a sample of 112 healthy pregnancies. Predictive associations between 3 measures of fetal neurobehavioral functioning and their developmental trajectories to neurological maturation in the first weeks after birth were examined. Prenatal measures included fetal heart rate (FHR) variability, fetal movement, and coupling between fetal motor activity and heart rate patterning; neonatal outcomes include a standard neurologic examination ( n  =   97) and brainstem auditory evoked potential (BAEP; n  =   47). Optimality in newborn motor activity and reflexes was predicted by fetal motor activity, FHR variability, and somatic–cardiac coupling predicted BAEP parameters. Maternal pregnancy-specific psychological stress was associated with accelerated neurologic maturation.     

The relation between neonatal heart period patterns and developmental outcome

Developmental psychophysiologists have long been interested in a means for evaluating infants at risk for cognitive disabilities. The current research addressed the utility of a noninvasive measure of cardiac vagal tone in predicting developmental outcome. At 40 weeks conceptional age, 3 min of resting EKG were recorded from 80 infants. Four groups of infants were evaluated: prematures who had no medical complications in the postnatal period; prematures who experienced respiratory distress syndrome during the postnatal period; term infants who experienced birth asphyxia during labor and/or postdelivery; and healthy term infants. The mental scale of the Bayley Scales of Mental Development was administered at 8 and 12 months conceptional age. Heart period data were analyzed to derive mean heart period, heart period variability, and estimates of vagal tone for each subject. Analyses of the relationship between the heart period variables and 8- and 12-month outcome (i.e., Bayley Scales) indicated that infants with high vagal tone at 40 weeks conceptional age always had positive developmental outcome at both eight and 12 months of age. Infants with low vagal tone had varied outcomes. Measures of medical complications and other measures of heart period variability were not related to developmental outcome. The results suggest that measurement of cardiac vagal tone may provide an important means for assessing risk in birth stressed populations.     

Prediction of five-year Stanford-Binet scores in preterm infants

The development of a group of 100 preterm infants, mean birth weight 1,877 grams, from a broad range of social class and ethnic backgrounds was followed from birth to age 5. Assessments in infancy were directed at medical problems and early perceptual, motor, social, and cognitive development. The child's performance on the Stanford-Binet test at age 5 could not be predicted from early hazardous events in the obstetrical or neonatal period. The results indicate that developmental outcome at age 5 could be predicted moderately from a single measure, infant visual attention, administered as early as term date. Prediction was improved by using a combination of assessments given during the first 9 months. Furthermore, prediction was significantly better for girls than for boys. Although moderate stability in performance was found for the group as a whole, prediction of an individual's performance resulted in a substantial number of children being misclassified. Social factors were more important than any other set of factors in relating to the child's mental performance at age 5.     

Development of the Stretch Reflex in the Newborn: Reciprocal Excitation and Reflex Irradiation

The stretch reflex is a spinal cord pathway between a muscle's stretch receptors and its own motor units. This reflex is thought to play an important role in normal motor function, because it is unique as a monosynaptic pathway, and because its hyperactivity is a hallmark of many motor disorders. We previously reported a difference in the stretch reflexes in healthy newborn infants and nonambulatory individuals with cerebral palsy (CP): these reflexes are characterized by responses from the stretched muscle and from the reciprocal or antagonist muscle. We proposed the existence of a functional spinal cord pathway that connects both agonist and antagonist muscles at a single joint. We hypothesized that this "reciprocal excitation" is a functional pathway of all newborn infants, which during the normal course of development of motor skills in infants is eliminated. If the CNS is damaged at birth, as in CP, the pathway of reciprocal excitation endures and is reinforced. In the current study of newborns, we recorded stretch reflex responses from all major muscle groups of the lower limb. This "irradiation of reflexes" is a normal phenomenon of the newborn CNS. This pathway becomes suppressed during normal maturation and control of coordinated limb movements.     

Differences on Bayley's infant behavior record for a sample of high-risk infants and their controls

3 groups of high-risk newborns and their controls were assessed at 92 weeks post-conceptional age using Bayley's Infant Behavioral Record (IBR). The 3 groups of high-risk infants were those who weighed 1,500 grams or less at birth and required no ventilator therapy, those weighing 1,500 grams or less at birth who required ventilator therapy, and newborns weighing more than 1,500 grams at birth who required ventilator therapy. Controls were healthy term infants matched for 7 socioeconomic and demographic variables. The first principal component of the IBR ratings for the 3 groups of high-risk infants and the controls were similar. All 3 groups of high-risk infants received less desirable IBR ratings on most items than their controls. In addition, there were some differences among high-risk groups; ventilated infants regardless of birth weight received the lowest ratings reflecting overall performance on the IBR, very low birthweight, ventilated newborns were more likely to receive ratings characterizing an overly active infant with a short attention span, and very low birth-weight, never-ventilated infants were most likely to be rated as happy but passive and delayed. The differences between the high-risk infants and controls in large part resulted from infants who were also delayed in terms of their mental and motor development.     

Fetal Antecedents of Infant Temperament

This study established the emergence of stable individual differences in neurobehavioral functioning prior to birth and examined their relation to subsequent infant temperament. Fetal heart rate and movement were recorded longitudinally for 31 fetuses at 6 gestational ages beginning at 20 weeks' gestation. Maternally reported temperament data were collected at 3 and 6 months. Moderate stability in all measures except reactivity was apparent at some time before birth. By 36 weeks, fetal neurobehavior accounted for between 22% and 60% of the variance in prediction of temperament scores. In general, more active fetuses were more difficult, unpredictable, unadaptable, and active infants. Higher fetal heart rate was associated with lower emotional tone, activity level, and predictability. We conclude that features of fetal neurobehavior provide the basis for individual differences in reactivity and regulation in infancy.     

Electroencephalogram and Heart Rate Regulation to Familiar and Unfamiliar People in Children With Autism Spectrum Disorders

Few studies have examined whether familiarity of partner affects social responses in children with autism. This study investigated heart rate regulation (respiratory sinus arrhythmia [RSA]: The myelinated vagus nerve's regulation of heart rate) and temporal–parietal electroencephalogram (EEG) activity while nineteen 8- to 12-year-old children with autism and 14 controls viewed videos of a familiar and an unfamiliar person reading a story. Children with autism had lower overall RSA levels and exhibited decreased RSA to the unfamiliar person, versus control children. Both groups decreased temporal–parietal EEG activity to the unfamiliar person. Higher RSA was related to higher social skill ratings and fewer problem behaviors. Thus, the social difficulties of children with autism may be characterized by specific mobilization to unfamiliar people.     

The motor and cognitive development of overweight preschool children

The aim of this study was to investigate the development of overweight compared with healthy-weight children attending kindergartens in Munich, Germany. Mean age of the children at the beginning of the study was 53.2 months (SD?=?7.5); the duration of the study was 20 months. At the beginning of the study children were classified as overweight (n?=?32) or healthy weight (n?=?318) using BMI scores. Dependent variables were aspects of physical growth, physical fitness, body coordination, manual dexterity, and cognitive performance. A higher rate of socially disadvantaged children was overweight compared with socially advantaged children. There was no association between weight and sex. Motor skills improved over trials. Socially disadvantaged and overweight children performed less well in gross motor skills compared with children from backgrounds of higher socioeconomic (SE) status or healthy-weight children. There was also an association between weight and socioeconomic status: overweight children of lower SE status performed less well compared with overweight children of upper SE status in all gross motor tasks. No connection could be found between weight and manual dexterity and cognitive performance.     

Gene-environment contributions to the development of infant vagal reactivity: the interaction of dopamine and maternal sensitivity

This study investigated dopamine receptor genes (DRD2 and DRD4) and maternal sensitivity as predictors of infant respiratory sinus arrhythmia (RSA) and RSA reactivity, purported indices of vagal tone and vagal regulation, in a challenge task at 3, 6, and 12 months in 173 infant-mother dyads. Hierarchical linear modeling (HLM) revealed that at 3 and 6 months, RSA withdrawal in response to maternal separation was greater (suggesting expected physiological regulation) in infants without the DRD2 risk allele than those with the risk allele. At 12 months, infants with the risk allele who were also exposed to maternal sensitivity showed levels of RSA withdrawal comparable to infants who were not at genetic risk. Findings demonstrate the importance of developmental analysis of gene-environment interaction.     

Behavior of Infants with Iron-Deficiency Anemia

This study tested the hypothesis that infants with iron-deficiency anemia show behaviors, such as increased proximity to caregivers, increased wariness or hesitance, and decreased activity, that could contribute to “functional isolation.” The behavior of 52 Costa Rican 12- to 23-month-old infants with iron-deficiency anemia was contrasted with that of 139 comparison group infants with better iron status during free play and mental and motor testing and in the home. Infants with iron-deficiency anemia maintained closer contact with caregivers; showed less pleasure and delight; were more wary, hesitant, and easily tired; made fewer attempts at test items; were less attentive to instructions and demonstrations; and were less playful. Adult behavior also differed. The results indicate that iron-deficiency anemia in infancy is associated with alterations in affect and activity, suggesting that functional isolation is a useful framework for understanding poorer developmental outcome in iron-deficiency anemia, the world's most common single nutrient deficiency.     

Mother–Infant Vagal Regulation in the Face-To-Face Still-Face Paradigm Is Moderated by Maternal Sensitivity

Parents' physiological regulation may support infants' regulation. Mothers ( N = 152) and 6-month-old male and female infants were observed in normal and disrupted social interaction. Affect was coded at 1-s intervals and vagal tone measured as respiratory sinus arrhythmia (RSA). Maternal sensitivity was assessed in free play. Mothers and infants showed opposite patterns of RSA change. During disrupted interaction, mothers' RSA increased and infants' decreased, suggesting self-regulation of distress. During reunion, although the typical pattern was for infants to return to baseline levels, infants of sensitive mothers and sensitive mothers both showed a significant decrease in RSA from baseline. Mothers' and infants' physiological responses may be a function of mutual responsiveness.     

Deficits in visual recognition in low birth weight infant pigtailed monkeys (Macaca nemestrina)

15 low birth weight and 15 normal birth weight pigtailed monkey infants were administered an adaptation of a standardized test of visual recognition memory, originally developed for human infants. Animals were given a series of problems in which 2 identical black-and-white patterns were presented for a familiarization period. The previously exposed pattern was then paired with a novel one, and looking time to each pattern was recorded. The normal birth weight animals directed a significant amount of their visual attention to the novel stimuli, thus demonstrating recognition abilities. As a group, the performance of the low birth weight infants remained at chance. These findings have important implications for an animal model to examine factors contributing to poor cognitive outcome in low birth weight human infants.     

Infant visual sustained attention and respiratory sinus arrhythmia

Infants were studied cross-sectionally at 14, 20, and 26 weeks of age. They were presented with varying and complex patterns on a TV screen. Two-thirds of the presentations were accompanied by an "interrupting stimulus" in the periphery delayed in time from the onset of fixation on the central stimulus. The infants were not easily distracted from looking at the central stimulus when the presentation of the interrupting stimulus occurred at the point of maximal heart rate (HR) deceleration. However, if the presentation occurred at the end of the HR response, the infants were easily distracted. Infants with large amounts of respiratory sinus arrhythmia (RSA; i.e., HR variability) in a baseline recording were less distractible during the deceleration-defined trials than were infants with low amounts of RSA. High-RSA infants also showed larger HR deceleration on these trials than did the low-RSA infants. These results are consistent with a model positing that sustained HR lowering during visual fixation is an index of active attention and that RSA is an index of voluntary, sustained attention in infants.     

Developmentally appropriate parent training for families with young children

In an effort to explore the value and feasibility of teaching the principles behind developmentally appropriate practices to parents, 53 families with young children were studied. Parents were randomly assigned to participate or not participate in a three month-long, weekly, parent training program. Following completion of the program members of participating families were less likely to engage in conflict during a puzzle solving task than were members of nonparticipating families. Parents who participated were more likely to take a supportive leadership role and have age-appropriate expectations during a puzzle solving task than were nonparticipating parents. Children in participating families showed better social skills than children in nonparticipating families. Portions of the increase in social skills were related to reductions in family conflict and to the development of a task orientation that was more appropriately focused on process than outcome. Lower family conflict was also related to better gross motor skills in children.     

Resting state networks mediate the association between both cardiovascular fitness and gross motor skills with neurocognitive functioning

Recent evidence suggests that cardiovascular fitness and gross motor skill performance are related to neurocognitive functioning by influencing brain structure and functioning. This study investigates the role of resting-state networks (RSNs) in the relation of cardiovascular fitness and gross motor skills with neurocognitive functioning in healthy 8- to 11-year-old children (n = 90, 45 girls, 10% migration background). Cardiovascular fitness and gross motor skills were related to brain activity in RSNs. Furthermore, brain activity in RSNs mediated the relation of both cardiovascular fitness (Frontoparietal network and Somatomotor network) and gross motor skills (Somatomotor network) with neurocognitive functioning. The results indicate that brain functioning may contribute to the relation between both cardiovascular fitness and gross motor skills with neurocognitive functioning.     

Interindividual Differences in Neonatal Imitation and the Development of Action Chains in Rhesus Macaques

The capacity to imitate facial gestures is highly variable in rhesus macaques and this variability may be related to differences in specific neurobehavioral patterns of development. This study evaluated the differential neonatal imitative response of 41 macaques in relation to the development of sensory, motor, and cognitive skills throughout the 1st month of life. The results show that infants who imitate facial gestures display more developed skills in goal-directed movements (reaching–grasping and fine hand motor control) than nonimitators. These differences might reflect, at least in part, the differential maturation of motor chains in the parietal and motor cortices, which partly overlap with those of the mirror neuron system. Thus, neonatal imitation appears to be a predictor of future neurobehavioral development.     

Pregnancy and delivery for women with a history of child sexual abuse

OBJECTIVE: To study whether women with a history of child sexual abuse are at increased risk of delivering low birth weight infants. Secondary aims were to study smoking habits, obstetric complications, health care use, and health complaints during pregnancy among women with a history of child sexual abuse. METHOD: In a case control study, 82 women with birth of a low birth weight infant (< 2500 g) (cases) and 91 women with birth of a normal birth weight infant (controls) were interviewed about experiences of child sexual abuse. RESULTS: Fourteen percent of the women disclosed a history of child sexual abuse involving at least genital touch. Birth of a low birth weight infant was not associated with a history of child sexual abuse (OR 1.03, 95% CI .44-2.40). More women with a history of child sexual abuse were smokers during pregnancy (56% vs. 31%) compared with nonabused women. Abused women reported lower age at menarche and sexual debut. Nonscheduled contacts with the antenatal care clinic and discomfort during pregnancy were more frequent among abused women when controlled for low birth weight. CONCLUSIONS: Women who delivered low birth weight infants were not more likely to have experienced child sexual abuse than women who delivered nonlow birth weight infants. Abused women were unemployed and daily smokers more often than nonabused women. Some of the abused women reported more health complaints, and more use of health care services during pregnancy, but did not have more obstetric complications during pregnancy and delivery.