Physical activity does not attenuate the relationship between daily cortisol and metabolic syndrome in obese youth.

OBJECTIVE: We examined the associations among daily cortisol, physical activity (MVPA) and continuous metabolic syndrome score (cMetS) in obese youth. METHODS: Fifty adolescents (mean age 14.8 ± 1.9 years) were recruited from medical clinics. Daily MVPA (min/day) was assessed by accelerometry. Saliva was sampled at prescribed times: immediately upon waking; 30 min after waking; and 3, 6 and 9 h after waking. Fasting lipids, glucose, waist circumference and blood pressure were used to calculate a continuous metabolic syndrome score (cMetS). Multiple linear regression analysis was used to examine associations among variables. RESULTS: The mean cMetS score was 4.16 ± 4.30 and did not differ by clinic or sex. No significant relationship was found between cortisol area under the curve (cAUC) and cMetS, nor did the interaction of MVPA with cAUC significantly predict cMetS. CONCLUSIONS: Physical activity, cortisol, and metabolic risk were not associated in this sample of obese adolescents. Future research should examine the role of insulin sensitivity in these relationships.

Toddlers with Early Behavioral Problems at Higher Family Demographic Risk Benefit the Most from Maternal Emotion Talk.

OBJECTIVE: To test the hypothesis that toddlers at highest risk for behavioral problems from the most economically vulnerable families will benefit most from maternal talk about emotions. METHODS: This study included 89 toddlers and mothers from low-income families. Behavioral problems were rated at 2 time points by masters-level trained Early Head Start home visiting specialists. Maternal emotion talk was coded from a wordless book-sharing task. Coding focused on mothers' emotion bridging, which included labeling emotions, explaining the context of emotions, noting the behavioral cues of emotions, and linking emotions to toddlers' own experiences. Maternal demographic risk reflected a composite score of 5 risk factors. RESULTS: A significant 3-way interaction between Time 1 toddler behavior problems, maternal emotion talk, and maternal demographic risk (p = .001) and examination of slope difference tests revealed that when maternal demographic risk was greater, more maternal emotion talk buffered associations between earlier and later behavior problems. Greater demographic risk and lower maternal emotion talk intensified Time 1 behavior problems as a predictor of Time 2 behavior problems. The model explained 54% of the variance in toddlers' Time 2 behavior problems. Analyses controlled for maternal warmth to better examine the unique contributions of emotion bridging to toddlers' behaviors. CONCLUSION: Toddlers at highest risk, those with more early behavioral problems from higher demographic-risk families, benefit the most from mothers' emotion talk. Informing parents about the use of emotion talk may be a cost-effective, simple strategy to support at-risk toddlers' social-emotional development and reduce behavioral problems.

Emerging effortful control in infancy and toddlerhood and maternal support: A child driven or parent driven model?

This study examined the association between children's temperamental characteristics of rudimentary effortful control (EC) and mothers' supportive reactions to their children's negative emotions in infancy and toddler period. One hundred and fifty eight (78 girls) Taiwanese children's EC was assessed at 12 and 24 months with mothers' report on the very short-form scales of Infant Behavior Questionnaire (IBQ) and Early Childhood Behavior Questionnaire (ECBQ) respectively. The mothers also completed questionnaires to assess their comforting behaviors at 12 months and both comforting and cognitive assistance to their children's expression of negative emotions when the child was 24 months old. A structural model was used to examine within- and across-time relations between children's EC and the maternal support. The results showed continuity of EC related temperament from infancy to toddlerhood and the 12-month rudimentary EC positively predicted mothers' comforting and cognitive assistance at 24 months, suggesting that mothers modulate their use of support in accordance with their prior knowledge of their children's regulatory capacities. The results indicated an influence of infants' temperament on adult behaviors, supporting potential evocative child effects on mothers' emotion coaching behaviors.

Association of hypothalamic-pituitary-adrenal axis function with neuropsychological performance in children with mild/moderate asthma.

The present study examines the relationship between hypothalamic-pituitary-adrenal (HPA) axis function and child psychological/neuropsychological function in a group of children with mild to moderate asthma. The goal of the study was to determine whether child neuropsychological functioning and psychological functioning were associated with cortisol production in response to adrenocorticotropic hormone(ACTH) stimulation when assessed as area under the curve. Data for this study were gathered from 63 children who participated in an ancillary study within the Childhood Asthma Management Program (CAMP) during the pre-randomization phase of the CAMP trial. At 2 of the 8 CAMP clinical centers participants completed an ACTH stimulation test after an overnight stay in the General Clinical Research Center. Gender differences on baseline cortisol and change in cortisol 30 minutes after infusion of ACTH were present. Results further indicated significant associations between cortisol production and measures of child neuropsychological function. Stepwise multiple regression analysis revealed that cortisol change could be predicted by measures of gender, working memory, and arousal maintenance, providing support for the hypothesis that cortisol plays a modest role in the neuropsychological function of children with mild and moderate asthma. In contrast, cortisol production was not associated with child reports of psychological functioning. Limitations to the methods employed in this study are discussed.

The influence of emotion regulation, level of shyness, and habituation on the neuroendocrine response of three-year-old children.

The current study investigated the temperamental dispositions of 53 three-year-old children (27 males, 26 females) and their behavioral and physiological responses to a stranger approach situation. Results indicated that elevations in cortisol were predicted by the child's level of shyness (with both shy and bold children showing elevations), better emotion regulation, and attendance at daycare which was believed to measure habituation to interactions with unknown adults in a playroom setting. In addition, the majority of children, both shy and bold, had cortisol levels that had begun to recover by fifteen minutes after the initial assessment. This suggests that the major concern for inhibited children is not weak regulation, but rather more frequent activation of the HPA system in response to novelty and a perceptual framework that expects fear.

Infant stress and parent responsiveness: regulation of physiology and behavior during still-face and reunion.

This study examined infant response and recovery from a social challenge and parent responses. Behavioral and physiological responses were measured from forty-three 5- and 6-month-olds infants during a modified still-face procedure that used an additional still-face reunion sequence. Results confirm the hypothesis that infants of more responsive parents show more regulation than infants of less responsive parents. Infants of more responsive parents showed greater regulation of heart rate and negative affect during the final episode of the procedure than infants of less responsive parents. In addition, this procedure elicited a cortisol response (from .22 microg/dl to .31 microg/dl). Findings suggest important links between parent behavior and infant stress reactivity and regulation.

The influence of temperamental reactivity and situational context on the emotion-regulatory abilities of 3-year-old children.

Although much research has been conducted on emotion regulation, little work in the preschool period has examined the interrelationships between emotion regulation, temperamental reactivity, and situational context. The authors investigated the temperamental dispositions of fifty-three 3-year-old children (27 boys, 26 girls) and their behavioral responses to several challenging tasks (i.e., stranger-approach situation, busy-caregiver paradigm, and delay-of-gratification task). Results indicated that both situational context and temperamental reactivity influenced the type of emotion-regulatory strategy used and that those relationships were best understood within a developmental framework. Moreover, the authors found that girls displayed more comforting strategies, suggesting that gender differences in emotion regulation may exist.

Attunement of maternal and child adrenocortical response to child challenge.

Although a great deal is known about physiological responding to stress in nonhuman animals, and also about individual differences in behavioral attunement in humans, physiological attunement between human mothers and their children has never been studied. The current study examined attunement in adrenocortical response between mother and child in the context of the child's exposure to a novel and potentially challenging task. Children ranging in age from two to four years of age walked on a balance beam for the first time while mothers watched on a monitor from the next room. Saliva samples were collected from both mothers and children before and 30 minutes following the beam walk. Individual differences in behavioral attunement were assessed from a videotaped mother-child teaching task, and coded for maternal sensitivity. We expected that mothers rated as highly sensitive would show better physiological attunement with their children's adrenocortical response to the balance beam walk than less sensitive mothers. We did not expect that all children would show a cortisol elevation in response to the task. Rather, we were interested in the degree to which mothers "matched" children's adrenocortical fluctuations, regardless of elevations or decreases in cortisol. Results supported the hypothesis. In the highly sensitive group, mothers' and children's adrenocortical responses to the child beam walk were significantly correlated, and in the less sensitive group the responses were not significantly related. Findings suggest that physiological attunement may co-occur with behavioral sensitivity in normal mother-child relationships.