Tonic hyper-connectivity of reward neurocircuitry in obese children.

OBJECTIVE: Obese children demonstrate less activation in prefrontal regions associated with self-control and inhibition when presented with food cues and advertisements. This study evaluates the differences between obese and healthy weight children in resting-state functional connectivity to these brain regions.

METHODS: Seed regions in bilateral middle frontal gyri were chosen based on previous task-based analysis showing differences between obese and healthy weight children's responses to food-associated stimuli. Functional connectivity to these seed regions was measured in resting-state scans collected in obese and lean children undergoing fMRI.

RESULTS: Obese children exhibited greater resting-state functional connectivity than healthy weight children between the left middle frontal gyrus and reward-related regions in the left ventromedial prefrontal cortex, as well as the left lateral OFC.

CONCLUSION: Previously published results demonstrated that obese children exhibit less activity in brain regions associated with self-control when viewing motivationally salient food advertisements. Here, it is shown that the obese children also have tonically greater input to these self-control regions from reward neurocircuitry. The greater functional connectivity between reward and self-control regions, in conjunction with weaker activation of self-control neurocircuitry, may render these children more susceptible to food advertisements, placing them at elevated risk for over-feeding and obesity.