The role of impulsivity and binge eating in outpatients with overweight or obesity. A temporal discounting trial

Abstract Background: Binge eating (BE) is associated with a range of cognitive control deficits related to impulsivity, including lower response inhibition, preference for immediate gratification, and maladaptive decision-making. The aim was to investigate whether impulsivity and BE may interact with the decision process and underlying brain activity in obese or overweight outpatients who are starting a treatment to achieve weight loss. Methods: A sample of 26 treatment-seeking obese and overweight outpatients with and without BE was evaluated for impulsivity, binge eating, and temporal discounting rates. Impulsivity was measured with the Barratt Impulsiveness Scale (BIS-11), binge eating with the Binge Eating Scale (BES), and changes in subjective value of rewards with the Temporal Discounting Task (TDt). Brain activity was recorded through high-density electroencephalogram (hd-EEG) during the TDt. Results: Patients with BE reported more impulsive tendencies and perceived sooner rewards as more gratifying when both options were delayed (p=0.02). The reward choice in the TDt was accompanied by an EEG alpha rhythm desynchronization in parietal areas. Conclusions: The tendency to favor immediate rewards may constitute an obstacle for obtaining adherence to treatment plans and to achieve weight loss goals for obese or overweight outpatients. Clinicians are therefore encouraged to include psychological outcomes such as impulsivity and dysfunctional eating behaviors when designing a weight loss program. Trial registration: This study was approved by the Ethics Committee of the Department of Psychological, Health, and Territorial Sciences of the University G. d’Annunzio of Chieti-Pescara (Prot. n. 254 of 03/14/2017)