A long-term analysis of hundreds of adolescent brains suggests that the socioeconomic status (SES) of a child’s family may play a role in the development of key brain areas responsible for learning, language, and emotional development.

To study the effects between a parent’s income and education levels and their child’s cognitive development, researchers from the National Institute of Mental Health scanned the brains of more than 600 individuals over the course of their lives between the ages of five and 25. They then compared these neuroimages against data on their parents’ education and occupation, as well as each participants’ IQ.  

When it comes to the relationship between brain anatomy and SES, little changes from childhood to early adulthood. This led researchers to believe that preschool life is a pivotal time in which associations between socioeconomic status and brain organization first begins to develop. SES was shown to be positively associated with total grey matter volume and less consistently with white matter volume. It was also associated with volume levels in the prefrontal cortex, the area of the brain associated with personality development, and the emotion-regulating hippocampus.

“We found positive associations between SES and total volumes of the brain, cortical sheet, and four separate subcortical structures,” wrote the authors in the Journal of Neuroscience, adding that the areas of the brain responsible for emotional development, learning, and language skills were more complex in people whose parents were more educated and worked in professional careers.

The science community has long known that childhood SES impacts cognitive development and mental health, but how it changes certain structures in the brain has not been well characterized.

“Early brain development occurs within the context of each child’s experiences and environment, which vary significantly as a function of socioeconomic status (SES),” wrote the authors. Early brain development is influenced by a child’s early life experiences and environment, which can vary depending on their family’s socioeconomic status, such as their parents’ income, education, and occupation. These factors have been shown to impact a child’s mental health, cognitive development, and their academic achievements. Understanding how such things physically change key structures within the brain could researchers understand how SES is associated with different life outcomes, such as health and achievement levels.

The study notes two important limitations: First, the team used an outdated measure of SES that doesn't necessarily encompass all parental SES factors. Secondly, the subjects in this sample are not representative of the full socioeconomic range in the United States. Furthermore, childhood socioeconomic status is a complex construct that influences the physical and psychosocial environment in which a child develops.

"Our findings inform ongoing efforts to clarify the spatiotemporal patterning of SES-related neuroanatomical variation and its relation to cognitive outcomes such as IQ," conclude the authors, noting that this link between SES and cognitive development "represents only one possible set of interactions between childhood environment, anatomy, and cognition."