Schienle Anne, Schäfer Axel, Hermann Andrea, Vaitl Dieter
Department of Psychology, University of Graz, Graz, Austria.
Biol Psychiatry. 2009 Apr 15;65(8):654-61. doi: 10.1016/j.biopsych.2008.09.028. Epub 2008 Nov 8.
The underlying neurobiological mechanisms that account for the onset and maintenance of binge-eating disorder (BED) are not sufficiently understood. This functional magnetic resonance imaging (fMRI) study explored the neural correlates of visually induced food reward and loathing.
Sixty-seven female participants assigned to one of four groups (overweight BED patients, overweight healthy control subjects, normal-weight healthy control subjects, and normal-weight patients with bulimia nervosa) participated in the experiment. After an overnight fast, the participants' brain activation was recorded during each of the following three conditions: visual exposure to high-caloric food, to disgust-inducing pictures, and to affectively neutral pictures. After the fMRI experiment, the participants rated the affective value of the pictures.
Each of the groups experienced the food pictures as very pleasant. Relative to the neutral pictures, the visual food stimuli provoked increased activation in the orbitofrontal cortex (OFC), anterior cingulate cortex (ACC), and insula across all participants. The BED patients reported enhanced reward sensitivity and showed stronger medial OFC responses while viewing food pictures than all other groups. The bulimic patients displayed greater arousal, ACC activation, and insula activation than the other groups. Neural responses to the disgust-inducing pictures as well as trait disgust did not differ between the groups.
This study provides first evidence of differential brain activation to visual food stimuli in patients suffering from BED and bulimia nervosa.
导致暴饮暴食症（BED）发作和维持的潜在神经生物学机制尚未得到充分理解。这项功能磁共振成像（fMRI）研究探讨了视觉诱发的食物奖励和厌恶的神经关联。
67名女性参与者被分配到四组之一（超重的暴饮暴食症患者、超重的健康对照受试者、体重正常的健康对照受试者和体重正常的神经性贪食症患者）参与实验。在禁食过夜后，在以下三种情况下记录参与者的大脑激活情况：视觉暴露于高热量食物、厌恶诱发图片和情感中性图片。在fMRI实验后，参与者对图片的情感价值进行评分。
每组都认为食物图片非常令人愉悦。相对于中性图片，视觉食物刺激在所有参与者的眶额皮质（OFC）、前扣带回皮质（ACC）和脑岛中引起了增强的激活。暴饮暴食症患者报告奖励敏感性增强，并且在观看食物图片时比所有其他组表现出更强的内侧OFC反应。神经性贪食症患者比其他组表现出更大的唤醒、ACC激活和脑岛激活。各组对厌恶诱发图片的神经反应以及特质厌恶没有差异。
这项研究首次提供了证据，证明暴饮暴食症和神经性贪食症患者对视觉食物刺激的大脑激活存在差异。
