Attentional Bias, "cool" and "hot" Executive Functions in Obese Patients: Roles of Body Mass Index, Binge Eating, and Eating Style

Purpose/Background Obesity is recognized as an important risk factor for many chronic diseases and is a major health issue. The current study examined attentional bias to food and the "cool" (inhibitory control and mental flexibility) and "hot" (affective decision making) executive functions (EFs) in obese patients preparing for bariatric surgery. In addition to body mass index (BMI), this study examined the impact of the binge-eating tendency and eating styles. Methods The study population comprised 21 morbidly obese patients preparing to undergo bariatric surgery (BMI ≥30 kg/m²) and 21 normal-weight controls (24 kg/m² > BMI ≥ 18.5 kg/m²). The Visual Probe Task was adopted to examine attentional bias toward food-related cues. The Stop-Signal Task and the Color Trails Test were used to assess inhibitory control and mental flexibility, respectively. The Iowa Gambling Task was administered to assess the affective decision making. Results (1) The obese patients showed poorer performances on cool EFs (for Color Trails Test, P = 0.016, η_p² = 0.136; for Stop-Signal Task, P = 0.049, η_p² = 0.093) and hot EF (for Iowa Gambling Task, normal controls showed progressed performance, P = 0.012, η_p² = 0.077, but obese patients did not show this progress, P = 0.111, η_p² = 0.089) compared with the normal controls; (2) participants with low binge-eating tendency had larger attentional biases at 2000 milliseconds than at 200 milliseconds on food-related cues (P = 0.003, η_p² = 0.363); and (3) low-restrained participants exhibited attentional bias toward the low-calorie food cues, compared with the high-restrained group (P = 0.009, η_p² = 0.158). Conclusions The current study contributes to the development of a different therapeutic focus on obese patients and binge eaters.