EEG Prefrontal Asymmetry in Weight Gain Prone College Students

Background: Obesity is a continuously emergent epidemic in the Western world, but little is known of the nature of weight gain proneness. Knowledge of predisposing factors and biological correlates of weight gain is necessary for curbing the impact of the obesity epidemic. History of dieting and weight (body mass index) are shown to be reliable predictors of future weight gain. Furthermore, both human and animal literature suggests that differential activation in the left- and right- prefrontal cortices may be correlated with obesity or suggestive of some propensity toward weight gain. Based on this extant literature, it is hypothesized that individuals of different weights and different dieting histories will show differential brain activation at rest. Objectives: This study examined brain activation at rest in participants with a history of dieting versus those with no history of dieting across a broad weight range. Hypotheses: Those higher in body mass index (BMI) were hypothesized to demonstrate greater left-prefrontal asymmetry compared those in a lower weight range. Dieting status was expected to moderate the relationship between weight and prefrontal asymmetry such that overweight dieters would show marked left prefrontal asymmetry and low weight dieters would show right prefrontal asymmetry. An exploratory analysis explored the main effect of dieting history on prefrontal lateralization. Methods: A total of 60 participants were recruited from Drexel University and the surrounding Philadelphia community. Participants demonstrated a history of dieting or no history of or current dieting. Participants were in the normal to overweight BMI range (20-30 kg/m2). Prefrontal asymmetry was assessed using a 25-electrode EEG array during rest with eyes open and eyes closed in an alternating design. These data assessed the utility of prefrontal asymmetry to predict dieting history and weight. Results: There was no significant relationship observed between dieting history and prefrontal asymmetry, nor BMI and prefrontal asymmetry. Likewise, no relationship was observed between BMI, dieting history and prefrontal asymmetry with the inclusion of PFS, Restraint, Positive Affect and Negative Affect as covariates. However, an exploratory analysis revealed that higher scores on Power of Food Scores confer greater left prefrontal asymmetry, while higher Revised Restraint Scores are associated with right prefrontal asymmetry. Discussion: This study suggests that dieting history and BMI, when not extreme, are not predictive of prefrontal asymmetry using EEG. However, measures associated with cognitive components of eating behavior are meaningful in predicting prefrontal asymmetry.M.S., Psychology -- Drexel University, 201