A study published in Psychological Science revealed a possible neurological explanation for why children from disadvantaged backgrounds are at risk for psychiatric problems. Children from disadvantaged neighborhoods showed blunted dorsal striatal activation — an area of the brain related to reward-motivation — during a task involving reward anticipation.
As study authors Teagan Mullins and associates say, the scientific literature points to a link between socioeconomic disadvantage and problematic mental health, yet few studies have directly looked at how neighborhood deprivation relates to brain function.
“Given the established link between socioeconomic disadvantage and psychopathology, it is critical to better understand the neurodevelopmental mechanisms driving this association,” Mullins and team say.
Children growing up in disadvantaged areas have less access to rewards, and there is evidence to suggest that these children show abnormalities in areas of the brain that relate to reward-motivation. To explore this, the researchers conducted a study using data from an extensive brain development study, involving a representative sample of American children.
“The Adolescent Brain Cognitive Development (ABCD) study provides an unprecedented opportunity to specify the relationship among deprivation, psychopathology and motivational-neurocircuit neurodevelopment,” the authors express.
The ABCD study involves numerous demographic and clinical assessments, including functional neuroimaging. The current study focused on children who had completed a monetary-incentive-delay (MID) functional MRI (fMRI) task, a task that requires quickly reacting to a stimulus in order to win, or refrain from losing, a reward. Additionally, the researchers analyzed data pertaining to psychopathology (using the Child Behavior Checklist (CBCL)), and neighborhood deprivation (using Census data). The final sample included 6,396 children between the ages of 9 and 10.
First, results showed that children from disadvantaged neighborhoods had higher internalizing and externalizing psychological problems.
Next, researchers analyzed fMRI activity during the MID-task and found a substantial association between neighborhood deprivation and decreased activation in certain subcortical structures of the brain. Specifically, children from disadvantaged areas showed decreased ventral striatal activation, dorsal striatal activation, and pallidum activation. These differences were seen during the reward anticipation segment of the task.
“In sum, higher neighborhood deprivation predicts blunted recruitment of motivational neurocircuits—particularly in the right hemisphere—during reward anticipation relative to neutral trials,” Mullins and team report.
Next, the results suggested an association between dorsal striatum recruitment during reward anticipation and children’s attention scores on the CBCL. After mediation modeling, it was found that “bilateral dorsal striatum recruitment significantly mediated the association between ADI and attention-problems.”
The authors discuss the implications of these findings. “Previous studies have found aberrant dorsal striatal morphology in children with attention-deficit/hyperactivity disorder extending into adolescence (Shaw et al., 2014) . . . Impaired reward-motivated behavior and attention problems can have devastating consequences as children progress through adolescence and adulthood (e.g., criminality, substance misuse), and specifying the mechanisms driving this relationship is a critical topic for facilitating evidence based intervention,” the researchers highlight.
Future longitudinal research is needed to establish causality concerning neighborhood deprivation, striatal activation, and attention problems in children.
The study, “Neighborhood Deprivation Shapes Motivational-Neurocircuit Recruitment in Children”, was authored by Teagan S. Mullins, Ethan M. Campbell, and Jeremy Hogeveen.
(Photo credit: Oscar Arias-Carrión et al.)