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Tonic hyper-connectivity of reward neurocircuitry in obese children.

ABSTRACT: 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.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.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.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.

SUBMITTER: Black WR

PROVIDER: S-EPMC4077951 | biostudies-literature | 2014 Jul

REPOSITORIES: biostudies-literature

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Tonic hyper-connectivity of reward neurocircuitry in obese children.

Black William R WR Lepping Rebecca J RJ Bruce Amanda S AS Powell Joshua N JN Bruce Jared M JM Martin Laura E LE Davis Ann M AM Brooks William M WM Savage Cary R CR Simmons W Kyle WK

Obesity (Silver Spring, Md.) 20140325 7

<h4>Objective</h4>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.<h4>Methods</h4>Seed regions in bilateral middle frontal gyri were chosen based on previous task-based analysis showing differences between obese and healthy weight children's resp ...[more]

PMID: 24634397

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Dataset Information

Tonic hyper-connectivity of reward neurocircuitry in obese children.

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Tonic hyper-connectivity of reward neurocircuitry in obese children.

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