Poverty, early care, and stress reactivity in adolescence: Findings from a prospective, longitudinal study in South Africa.

A considerable body of evidence suggests that early caregiving may affect the short-term functioning and longer term development of the hypothalamic-pituitary-adrenocortical axis. Despite this, most research to date has been cross-sectional in nature or restricted to relatively short-term longitudinal follow-ups. More important, there is a paucity of research on the role of caregiving in low- and middle-income countries, where the protective effects of high-quality care in buffering the child's developing stress regulation systems may be crucial. In this paper, we report findings from a longitudinal study (N = 232) conducted in an impoverished periurban settlement in Cape Town, South Africa. We measured caregiving sensitivity and security of attachment in infancy and followed children up at age 13 years, when we conducted assessments of hypothalamus-pituitary-adrenocortical axis reactivity, as indexed by salivary cortisol during the Trier Social Stress Test. The findings indicated that insecure attachment was predictive of reduced cortisol responses to social stress, particularly in boys, and that attachment status moderated the impact of contextual adversity on stress responses: secure children in highly adverse circumstances did not show the blunted cortisol response shown by their insecure counterparts. Some evidence was found that sensitivity of care in infancy was also associated with cortisol reactivity, but in this case, insensitivity was associated with heightened cortisol reactivity, and only for girls. The discussion focuses on the potentially important role of caregiving in the long-term calibration of the stress system and the need to better understand the social and biological mechanisms shaping the stress response across development in low- and middle-income countries.

In search of an adult attachment stress provocation to measure effect on the oxytocin system: a pilot validation study.

BACKGROUND: Oxytocin is a promising biomarker for psychiatric conditions arising from early relational trauma, childhood maltreatment, and attachment dysregulation, including posttraumatic stress and dissociative disorders. OBJECTIVE: This exploratory pilot study examined plasma oxytocin as a biomarker for alterations in the attachment system. DESIGN: We used a single group, repeated-measures design with 15 women. The protocol used a film clip previously validated as a provocation to the hypothalamic-pituitary-adrenal axis. RESULTS: The repeated-measures ANOVA showed differences in oxytocin across the three time points. Correlations with oxytocin indicated that measures of dissociation and somatization correlated most strongly with higher levels of oxytocin measured during exposure to the film's bonding scene and posttraumatic stress disorder correlated most strongly with lower levels at the film's abandonment scene. Post hoc analyses revealed differences in oxytocin response related to psychopathology. CONCLUSION: Replication studies should characterize participants on a range of psychiatric conditions associated with attachment dysregulation.

Examining infants' cortisol responses to laboratory tasks among children varying in attachment disorganization: stress reactivity or return to baseline?

Cortisol is a hormone involved in mounting a stress response in humans. The evidence of stress reactivity among young children has been mixed, however. In the present study, the order of two laboratory tasks (i.e., Strange Situation and play) was counterbalanced, and home saliva samples were obtained. Saliva samples were also collected upon the children's arrival at the laboratory and at 40, 65, and 80 min after arrival. The authors examined changes in cortisol using piecewise hierarchical linear modeling, testing whether observed increases reflected a return to baseline or stress reactivity. An interaction between attachment disorganization and task emerged, such that disorganized infants showed increases in cortisol in response to the stressor compared with play, whereas organized infants did not show cortisol reactivity to either task. Implications for the buffering effects of maternal care on stress reactivity are discussed.