Department of Psychiatry, New York State Psychiatric Institute, New York, USA.
Department of Psychiatry, Columbia University Irving Medical Center, New York, USA.
Psychol Med. 2022 Jul;52(9):1755-1764. doi: 10.1017/S0033291720003542. Epub 2020 Oct 13.
Restriction of food intake is a central feature of anorexia nervosa (AN) and other eating disorders, yet also occurs in the absence of psychopathology. The neural mechanisms of restrictive eating in health and disease are unclear.
This study examined behavioral and neural mechanisms associated with restrictive eating among individuals with and without eating disorders. Dietary restriction was examined in four groups of women ( = 110): healthy controls, dieting healthy controls, patients with subthreshold (non-low weight) AN, and patients with AN. A Food Choice Task was administered during fMRI scanning to examine neural activation associated with food choices, and a laboratory meal was conducted.
Behavioral findings distinguished between healthy and ill participants. Healthy individuals, both dieting and non-dieting, chose significantly more high-fat foods than patients with AN or subthreshold AN. Among healthy individuals, choice was primarily influenced by tastiness, whereas, among both patient groups, healthiness played a larger role. Dorsal striatal activation associated with choice was most pronounced among individuals with AN and was significantly associated with selecting fewer high-fat choices in the task and lower caloric intake in the meal the following day.
A continuous spectrum of behavior was suggested by the increasing amount of weight loss across groups. Yet, data from this Food Choice Task with fMRI suggest there is a behavioral distinction between illness and health, and that the neural mechanisms underlying food choice in AN are distinct. These behavioral and neural mechanisms of restrictive eating may be useful targets for treatment development.
限制食物摄入是神经性厌食症（AN）和其他饮食失调的核心特征，但也会在没有精神病理学的情况下发生。健康和疾病中限制进食的神经机制尚不清楚。
本研究检查了饮食限制在有和没有饮食失调的个体中的行为和神经机制。在四组女性中（n=110）检查了饮食限制：健康对照组、节食健康对照组、亚阈值（非低体重）AN 患者和 AN 患者。在 fMRI 扫描期间进行了食物选择任务，以检查与食物选择相关的神经激活，并进行了实验室餐。
行为研究结果区分了健康和患病参与者。健康个体，包括节食和非节食者，选择的高脂肪食物明显多于 AN 或亚阈值 AN 患者。在健康个体中，选择主要受美味度影响，而在两组患者中，健康状况发挥了更大的作用。与选择相关的背侧纹状体激活在 AN 患者中最为明显，并且与任务中选择较少的高脂肪选择以及第二天的膳食中摄入的卡路里减少显著相关。
从各组体重减轻的量逐渐增加，表明存在连续的行为谱。然而，这项 fMRI 食物选择任务的数据表明，疾病和健康之间存在行为差异，并且 AN 中食物选择的神经机制是不同的。这些限制进食的行为和神经机制可能是治疗开发的有用靶点。
