Developmental psychobiology最新文献

This study employed latent change score models to examine the co-changes and mutual influences of fearful temperament, task switching, and maternal intrusiveness in early childhood. Participants included 335 children (171 boys, 164 girls; M_age = 3.09 years at baseline; 77.3% White, 14.0% Black, 8.4% multiracial, 0.3% Asian, 7.8% Hispanic) and their mothers. Higher levels of maternal intrusiveness at 36 months predicted a smaller increase in children's task switching between 36 and 48 months. Higher levels of task switching at 36 months predicted a larger decrease in fearful temperament. The changes between task switching and fearful temperament co-occurred; as the degree of task switching increased, fearful temperament decreased, or vice versa. Family-oriented interventions that reduce maternal intrusiveness may facilitate children's improvements in task switching, which is closely associated with the development of a fearful temperament.

Early disruption of filial attachment appears to sensitize underlying threat-related processes to produce vulnerability for developing depression when encountering stressors later in life. Evidence indicates neuroinflammatory signaling mediates this effect, though exact mechanisms are poorly understood. In a guinea pig model, early periods of isolation from the mother produce depressive-like behavior and fever, which sensitize with repeated isolation. Because cyclooxygenase inhibitors reduce these effects, the sensitization appears to involve prostaglandins such as PGE-2. We asked if isolation increased central sensitivity to PGE-2, which could underlie the sensitization process. Experiment 1 established that intraventricular (ICV) infusion of 1 or 3 µg of PGE-2 increased depressive-like behavior in pups. The 3 µg dose also produced an initial suppression and then a rise in core temperature. In Experiment 2, repeated isolation of pups sensitized depressive-like behavior. Days later (early adolescence), 1 µg of ICV-PGE-2 increased depressive-like behavior in previously isolated guinea pigs, but not in non-previously isolated controls. Core temperature was unaffected. Thus, early isolation from the mother increased sensitivity of depressive-like behavior, but not fever, to PGE-2. Results suggest that increased sensitivity to PGE-2 could play a role in the enhanced vulnerability to depression in adolescents previously exposed to early attachment disruption.

In male hamsters, puberty is associated with increased serotonin innervation and unusual responses to fluoxetine, such as enhanced play-fighting activity against intruders but also an acceleration of its maturation from attacks focused on the face (frontal attacks) to the lower belly and rump, suggesting a role for serotonin (5-HT). We tested the role of 5-HT_1A and 5-HT₃ receptor subtypes on play-fighting behavior observed during resident intruder tests through peripheral treatment with receptor agonists and antagonists. Contrary to observations in adult hamsters, we did not observe any overarching effects of treatment on measures of play-fighting activity, nor its maturation from frontal attacks. However, secondary analyses highlighted variability within the datasets. A subgroup of animals presented inhibited play-fighting activity in response to treatment with DPAT, a 5-HT_1A receptor agonist, but these animals also showed enhanced locomotor activity and reduced interest in engaging their opponents. In addition, early juvenile agonistic behavior was predictive of responsiveness to other treatments. The 5-HT_1A receptor antagonist, WAY, caused a reduction in play-fighting activity in high attackers and an increase in low attackers. Though high attackers under pretest conditions were equally inhibited by CBG, a 5-HT₃ receptor agonist, they performed a higher proportion of frontal attacks. Finally, the density of 5-HT_1A and 5-HT₃ receptor immunoreactivity was compared among subjects sampled at postnatal Day 35 (early puberty) or postnatal Day 70 (adulthood) within areas mediating the control of social behavior in adults. Adult males showed a higher density of immunolabeling for 5-HT_1A receptors in the anterior hypothalamus and medial amygdala, as well as 5-HT₃ receptors in the lateral septum. The data suggest that the development of 5-HT receptor expression participates in the control of play-fighting activity and its maturation during puberty in male hamsters.

The experience of maltreatment in childhood is associated with poorer developmental and health outcomes. This may be explained by the capacity for maltreatment to dysregulate stress-responsive neurophysiological systems, including the hypothalamic–pituitary–adrenal (HPA) axis. This study presents the results of the first meta-analysis that examines the association between maltreatment and resting HPA-axis activity in children and the role of “third variables” in accounting for observed heterogeneity in this association. Analyses of 18 studies, including N = 2216 children, indicated that although there was no difference in resting HPA-axis activity between children who had been maltreated and those who had not (standardized mean difference [SMD] = 0.04), there was substantial heterogeneity in the association between maltreatment and HPA-axis activity across studies (I² = 58.60%, p = 0.001). Further analyses revealed that the association between maltreatment and resting HPA-axis activity was contingent upon the source of information regarding maltreatment (B = 0.33, p = 0.002) and the degree to which maltreated and comparison groups differed in their socioeconomic status (B = 0.39, p = 0.037).

This study evaluated information shared with parents about infant development through formal sources in five countries and international organizations (i.e., regions). Consistent findings among regions were: (1) Tendency to format information as developmental milestones; (2) Sharing primarily information about motor development, but most often repeating recommendations for advancing language development; (3) Variability in specific information shared among regions and among sources within each region about the same general topics; and (4) Consensus mentioning seven behaviors representing early exploratory, mobility, and communication abilities that support learning and expression. Differences in the content shared among the regions are also described. The findings provide insight into commonalities and differences in educational practices that likely reflect more universal versus regional cultural beliefs and values.