Impulsivity and neural mechanisms that mediate preference for immediate food rewards in people with vs without excess weight. (1st February 2022)

• Record Type: Journal Article
• Authors: Liu, Xing; Turel, Ofir; Xiao, Zhibing; He, Jinbo; He, Qinghua
• Is Part Of: Appetite. Volume 169(2022)
• Publication Date: 2022-02-01
• Subjects: Impulsivity -- Excess weight -- Delay discounting -- Food -- Neural mechanisms; BMI body mass index -- fMRI functional magnetic resonance imaging -- mPFC medial prefrontal cortex -- FP frontal pole -- ACC anterior cingulate cortex -- MFG middle frontal gyrus -- IFG inferiorfrontal gyrus -- vlPFC ventrolateral prefrontal cortex -- dlPFC dorsal lateral prefrontal cortex -- vmPFC ventromedial prefrontal cortex -- BIS-11 Barratt Impulsiveness Scale -- YFAS The Yale Food Addiction Scale -- MPRAGE magnetization prepared rapid gradient echo -- ROIs regions of interest; Food habits -- Periodicals; Appetite -- Periodicals; Appetite disorders -- Periodicals; Electronic journals; 306.4613
• DOI: 10.1016/j.appet.2021.105798
• Languages: English
• ISSNs: 0195-6663

Abstract

Abstract: People with excess weight (overweight or obese; body mass index [BMI]>25) are generally characterized as impulsive with regards to food. However, the underlying brain mechanisms of this impulsivity are not fully understood. As such, this study aims at understanding the neural mechanisms underlying impulsivity toward food rewards, as well as differences in delay discounting patterns for hypothetical food between people with vs without excess weight. To this end, participants (79 college students, 33 with excess weight and 46 without) performed a food delay discounting task and completed questionnaires related to food addiction and impulsivity. In the task, we manipulated the magnitude of immediate and delayed rewards and employed event-related fMRI design to measure brain activity. The results showed that people with excess weight, compared to those without, were more impulsive and presented a lower probability of choosing delayed rewards. The higher the BMI was, the lower the probability of choosing delayed rewards was. People with excess weight also had higher impulsivity scores than people with no excess weight. Moreover, people with excess weight had less activation in executive function areas such as the anterior cingulate gyrus, the frontal pole, and the inferior frontal gyrus in both difficult and easy decision-making conditions. These results suggest that hypo-activation of executive function areas may contribute to the progression of decision impulsivity in relation to food, which in turn is associated with excess weight. Highlights: People with excess weight chose less delayed rewards than those without excess weight. People with excess weight had higher scores than those without excess weight in the impulsivity scale. People with excess weight showed less activity in the ACC, Frontal pole, and IFG.