Stress-induced elevation of oxytocin in maltreated children: evolution, neurodevelopment, and social behavior

Abstract

Child maltreatment often has a negative impact on the development of social behavior and health. The biobehavioral mechanisms through which these adverse outcomes emerge, however, are not clear. To better understand the ways in which early life adversity affects subsequent social behavior, changes in the neuropeptide oxytocin (OT) in children (n = 73) aged 8.1-11.5 years following a laboratory stressor were examined. Girls with histories of physical abuse have higher levels of urinary OT and lower levels of salivary cortisol following the stressor when compared to controls. Abused and control boys, however, do not differ in their hormonal responses. These data suggest that early adversity may disrupt the development of the stress regulation system in girls by middle childhood.

Fig 1

Oxytocin release across the experimental timeframe in children. Oxytocin levels are significantly higher in maltreated girls than in control girls subsequent to the TSST-C. For the maltreated girls, oxytocin at the 30 minute sample is significantly higher than the baseline and 60 minute samples. No significant differences in oxytocin are observed between condition or across time for boys.

Fig 2

Cortisol levels are significantly lower in maltreated girls than it is in control girls. For the control girls, cortisol increased in response to the TSST-C, whereas maltreated girls show little if any cortisol change in response to the stressor. In contrast, maltreated and control boys show comparable cortisol profiles across time.