Anhedonia is an Important Mediator of Performance on the Iowa Gambling Task in Individuals With Obesity

Mood disorders may influence decision making in individuals with greater adiposity. The authors hypothesized that individuals with obesity with a high level of anhedonia have poorer decision making abilities, measured by performance on the Iowa Gambling Task (IGT). Data from 116 obese (≥30 kg/m2) individuals (50 men/66 women; 34 years ±9) completed the IGT, Physical Anhedonia Scale (PAS), Inventory for Depressive Symptomatology, and the Three Factor Eating Questionnaire (while on a weight maintaining diet. Lower IGT scores (i.e., poorer performance) were negatively associated with higher waist circumference (r = −.20; p = .035), greater anhedonia (r = −.33; p < .001) and, positively associated with cognitive restraint (ρ = .18; p = .05). In a multivariate linear model, only anhedonia remained associated (ß = −0.7; p = .02) with IGT score. With repetition, individuals with low levels of anhedonia improved their performance over the task (Z = −2.52; p = .02). Furthermore, individuals with low anhedonia displayed an advantageous learning pattern while those with high anhedonia did not show any indication of learning (F = 2.81; p = .02). These findings indicate a link between a lack of pleasure and adaptive decision making in individuals with greater adiposity.