An Epigenetic Mechanism for Differential Neural Maturation and Socio-emotional Development in Childhood

Forming adequate social bonds is critical for a healthy and prolonged life. Social maturity enhances successful social integration and is dependent upon a collection of perceptual and cognitive skills that develop throughout childhood. While social skills consistently improve with age, the rate of development varies between individuals. Trajectories of social development are likely influenced by a combination of biological and environmental factors.

Here we investigate epigenetic regulation of the endogenous oxytocin system as a biological marker of social perception and maturation. DNA methylation in the promoter of the oxytocin receptor gene (OXTRm) regulates expression of the molecule that allows an individual to make efficient use of oxytocin, resulting in social and emotional ramifications. Our lab has established that OXTRm can be assayed from saliva, shows significant variability in the population, is elevated in individuals with autism, and is associated with a wide range of behavioral and neural indices in infants and adults. However, little is known about the fine-tuning, maintenance, and influence of this system on the emergence of social behaviors cultivated during middle childhood. Using a neuroimaging epigenetic approach, this project examines individual variability in trajectories of socio-emotional development in neurotypical children. Specifically, we explore OXTRm as a marker for differential neural maturation that support self-regulation, empathy, and essential social skills.

For the first time, we find that OXTRm is associated with neural activity during a basic social perception task. We also demonstrate that indexes of children’s neural maturation during a prosocial movie and functional connectivity at rest are associated with OXTRm suggesting that the social environment may drive neurobiological differences in the rate of maturation. Lastly, the observed associations between neural maturity and OXTRm interact to predict children’s socio-emotional behaviors two years later in development indicating that these may be useful neurobiological markers for behavioral outcomes. Taken together, these findings provide evidence of epigenetic influence on the developing brain and can help inform future research that may lead to a better understanding of variability and earlier detection of children at risk for socio-emotional dysfunction.