Tonic hyper-connectivity of reward neurocircuitry in obese children

Obesity (Silver Spring). 2014 Jul;22(7):1590-3. doi: 10.1002/oby.20741. Epub 2014 Mar 25.

Abstract

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.

Keywords: children; functional magnetic resonance imaging (fMRI); impulsivity; orbitofrontal cortex; resting-state; ventromedial prefrontal cortex.

Publication types

  • Comparative Study
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Brain / physiology*
  • Brain Mapping / methods
  • Child
  • Cues
  • Female
  • Food*
  • Frontal Lobe / physiopathology*
  • Humans
  • Magnetic Resonance Imaging
  • Male
  • Motivation
  • Neural Pathways / physiopathology*
  • Obesity / physiopathology*
  • Photic Stimulation / methods
  • Reward*
  • Risk Factors