Oxytocin and the emergence of individual differences in the social regulation of stress

The Multifaceted Role of Oxytocinergic System and OXTR Gene

The article explores the multifaceted role of the neuropeptide oxytocin in human behavior and its connection to the oxytocin receptor ( OXTR ) gene. Oxytocin, produced in specific brain nuclei, is implicated in emotional, social, and maternal behaviors, stress reduction, uterine contraction during childbirth, and lactation. The OXTR gene, located on chromosome 3, encodes oxytocin receptors found in various body parts, including critical brain regions associated with social behaviors. The article delves into studies on rodents, revealing correlations between OXTR gene expression and pair bonding in the prefrontal cortex and social behavior regulation in the amygdala. The discussion extends to the impact of oxytocin on social support-seeking behavior, focusing on a specific genetic variation, rs53576. The article explores how this genetic variation influences empathy, stress reactivity, and susceptibility to disorders such as autism and social anxiety. Furthermore, the article examines structural and functional changes in the brain associated with OXTR gene variations. It discusses the role of DNA methylation in influencing oxytocin receptor availability, affecting social perception and responsiveness to negative stimuli. The article also highlights the oxytocinergic system's involvement in disorders such as autism and social anxiety, emphasizing the interplay between genetics and environmental factors. The article also touches on the potential therapeutic use of exogenous oxytocin in mitigating symptoms associated with these disorders. In summary, the article underscores the intricate relationship between oxytocin, the OXTR gene, and diverse aspects of human behavior, providing insights into social bonding, perception, and the development of behavioral disorders.

Oxytocin receptor genotype moderates the association between maternal prenatal stress and infant early self-regulation

INTRODUCTION

Maternal prenatal stress may have long-term adverse consequences for child development. Accumulating evidence shows that the oxytocin-receptor genotype may play a role in differential susceptibility to early-life adversity, but no studies have examined whether this moderation extends to the prenatal stress exposures.

METHODS

In the FinnBrain Birth Cohort Study, a sample of 1173 mother-child dyads were examined. We studied the possible moderating effect of the cumulative effect of infant oxytocin-receptor risk genotypes (rs53576GG and rs2254298A) in the association between maternal prenatal stress, and infant negative reactivity and emerging self-regulation at 6 months of age.

RESULTS

The number of OTr risk genotypes moderated the association between maternal prenatal anxiety and infant self-regulation, implying a cumulative effect of genotype, although effects sizes were small. In infants with two risk genotypes, a negative association between prenatal anxiety and self-regulation was observed, whereas in infants with one or no risk genotypes, the association between maternal prenatal anxiety and temperament was non-significant.

CONCLUSION

Oxytocin-receptor genotype may moderate the association of maternal stress during pregnancy and child social-emotional development. Possible mechanisms for this moderation effect are discussed. Further studies with a more comprehensive polygenic approach are needed to confirm these results.

Neurohormones and temperament interact during infant development

The infant's psycho-physiological regulatory system begins to develop prenatally and continues to mature during the postnatal period. Temperament is a construct comprising tonic individual differences in dispositional physiological and behavioural reactions as well as an evolving ability to regulate to environmental conditions. Theoretical models and research have shown that neurohormonal and -physiological factors contribute to individual development and impact infant behaviours as well as the developing regulatory system. Moreover, prenatal maternal risks such as stress and depression are thought to programme fetal regulatory tendencies and that influences neural and behavioural functioning in infancy. The purpose of this review is to examine the theories and research that link infant temperament to neurohormonal and -physiological development in typically developing infants and in those exposed to environmental risk. Research has demonstrated associations between individual variation in physiological stress responses and regulation (measured with cortisol). Moreover, studies have noted an association with physiological regulation and socio-emotional interaction (as measured by the touch-oxytocin link) that may buffer emotional dysregulation. The interaction between individual differences in temperamental tendencies, neurohormonal and -physiological patterns will be discussed by presenting data from studies that have shown that infant neurohormonal and -physiological functioning sets an important trajectory for the development of the individual.This article is part of the theme issue 'Diverse perspectives on diversity: multi-disciplinary approaches to taxonomies of individual differences'.