Reinforcement sensitivity and bulimia symptoms: the role of emotion regulation

Objective: Reinforcement Sensitivity Theory (RST) provides a theoretical foundation associated with various approach and avoidance behaviors and individual personality differences. Sensitivity to reward and punishment, two neural systems within the RST have been significantly associated with bingeing and purging behaviors. However, inconsistent findings are observed and specific factors mediating these relationships are not well understood. Deficits in emotion regulation may account for these relationships, as both negative urgency and distress tolerance have been independently associated with bulimia behaviors. Thus, this is an area that requires further investigation. Method: The current study utilized various self-report inventories, including the Eating Disorder Inventory-3rd Edition to measure bulimia symptoms, as well as measures of negative affect, sensitivity to reward and punishment, distress tolerance, and negative urgency. These measures were used to assess whether distress tolerance and negative urgency mediated associations between sensitivity to reward and punishment and bulimia symptoms in a community sample of 394 young adults ranging from the ages of 18 to 25. Results: As expected, sensitivity to reward and punishment were significantly associated with decreased distress tolerance. Distress tolerance was also directly associated with greater negative urgency, which was significantly associated with increased bulimia symptoms. Consistent with hypotheses, indirect associations between sensitivity to reward and sensitivity to punishment to bulimia symptoms via distress tolerance and negative urgency were observed, controlling for gender and negative affect. Discussion: Results contribute to understanding specific contributions of risk factors within the relationship of sensitivity to reward and punishment and bulimia symptoms, measured by the EDI-3. Novel to existing literature, results indicate that reinforcement sensitivity significantly contributes to emotion regulation deficits. Thus, these findings may have important implications for understanding the development and treatment of bulimia symptoms. Level of evidence: Level V, based on descriptive, cross-sectional data.