Neural vulnerability factors that increase risk for future weight gain

Area of Science:

• Neuroscience
• Obesity Research
• Behavioral Science

Background:

• Neural vulnerability factors are theorized to increase overeating and weight gain.
• Previous cross-sectional studies could not distinguish cause from effect regarding neural responsivity and overeating.

Purpose of the Study:

• To review evidence from prospective imaging and behavioral studies, and randomized experiments.
• To evaluate five neural vulnerability theories for excessive weight gain.
• To synthesize findings into a new working etiological model for obesity.

Main Methods:

• Review of prospective imaging and behavioral studies.
• Analysis of randomized experiments in humans and animals.
• Evaluation of evidence for five distinct neural vulnerability theories of obesity.

Main Results:

• Strong support for the incentive sensitization theory of obesity.
• Moderate support for reward surfeit, inhibitory control deficit, and dynamic vulnerability model theories.
• Minimal support for the reward deficit theory.

Conclusions:

• Existing data support a revised etiological model for obesity, integrating multiple neural vulnerability factors.
• The incentive sensitization theory is strongly supported.
• Future research directions are proposed to refine the working etiological model.