Asymmetric Brain Activation and its Relationship with Overeating (Paperback)

Dietary intake is heavily influenced by affect, which has been related to asymmetrical activation in the prefrontal cortex (prefrontal asymmetry). In normal weight individuals, dietary restraint has been related to prefrontal asymmetry. However, this relationship was not mediated by affect, suggesting an independent relationship between prefrontal asymmetry and eating behavior. This study tested the hypotheses that, in an obese sample, several markers of overeating would be related to prefrontal asymmetry independent of affect. EEG recordings, and measures of overeating and affect, were collected in obese adults. Regression analyses were used to predict prefrontal asymmetry from appetitive measures while controlling for affect. Cognitive restraint and binge eating were not associated with prefrontal asymmetry. However, disinhibition, hunger, and appetitive responsivity predicted left- sided prefrontal asymmetry independent of affect. Findings in this study further implicate the prefrontal cortex in the cognitive control of dietary intake. Models of human affect, overeating, prefrontal asymmetry, and how they may be related are discussed at length.