Characterizing impulsivity and resting-state functional connectivity in normal-weight binge eaters

Area of Science:

• Neuroscience
• Psychiatry
• Clinical Psychology

Background:

• Binge eating, characterized by uncontrolled eating episodes, is often associated with obesity and Binge Eating Disorder (BED).
• However, binge eating can also occur in normal-weight (NW) individuals, suggesting factors beyond weight status may be involved.
• Impulsivity is a potential contributing factor to binge eating onset and progression.

Purpose of the Study:

• To investigate impulsivity and functional brain connectivity in NW individuals with binge-eating episodes.
• To explore whether altered corticostriatal connectivity, implicated in impulsivity, is present in NW binge eaters, mirroring findings in BED patients.

Main Methods:

• A resting-state functional magnetic resonance imaging (fMRI) study was conducted on 39 NW men and women, categorized as binge eaters (BE) and non-BE.
• Brain functional connectivity was analyzed using graph theoretic centrality measures and seed-based analysis.
• Trait impulsivity was assessed via self-report questionnaires.

Main Results:

• The BE group demonstrated significantly higher trait impulsivity compared to the non-BE group.
• Reduced degree centrality was observed in the right middle frontal gyrus, left insula/putamen, and left temporoparietal regions in BE individuals.
• Lower functional connectivity was found between the right middle frontal gyrus and right insula in the BE group.

Conclusions:

• Altered functional connectivity and heightened impulsivity are associated with binge eating behavior, even in the absence of overweight or obesity.
• These findings extend the understanding of BED by highlighting the role of impulsivity independent of weight status.
• The results support the hypothesis that corticostriatal pathway alterations may underlie binge eating in a broader population.