Reward System Responses to Food Aromas: Effects of Obesity and Alcohol Intake

奖励系统对食物香气的反应：肥胖和酒精摄入的影响

• 批准号: 8664838
• 负责人: Robert V Considine
• 金额: $ 40.09万
• 依托单位: INDIANA UNIV-PURDUE UNIV AT INDIANAPOLIS
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-07-01 至 2016-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8664838
• 关键词: Acute; Affect; Alcohol consumption; Alcoholic Intoxication; Alcoholism; Alcohols; Amygdaloid structure; Area; Behavior; Behavioral Mechanisms; Behavioral inhibition; Body fat; Brain; Brain imaging; Calories; Cardiovascular Diseases; Circadian Rhythms; Consumption; Cues; Data; Desire for food; Development; Diabetes Mellitus; Diet; Disinhibition; Eating; Eating Behavior; Energy Intake; Exposure to; Fasting; Food; Food deprivation (experimental); Functional Magnetic Resonance Imaging; Hippocampus (Brain); Human; Hunger; Hyperphagia; Image; Imaging Techniques; Incentives; Individual; Ingestion; Insula of Reil; Intake; Malignant Neoplasms; Medial; Motivation; Obesity; Odors; Placebos; Process; Property; Public Health; Research; Rewards; Risk; Satiation; Sensory; Signal Transduction; Smell Perception; Stimulus; Study Subject; System; Testing; Woman; Work; alcohol effect; alcohol exposure; analog; blood oxygen level dependent; brain pathway; design; drinking; experience; feeding; food flavor; frontal lobe; hedonic; increased appetite; insight; loss of control over eating; neuroimaging; novel; problem drinker; relating to nervous system; response; restraint

DESCRIPTION (provided by applicant): Food aromas are powerful appetitive cues that are intrinsic to foods' flavor and hedonic qualities, and such cues can facilitate overeating. Alcohol consumption similarly "primes" appetite, and contributes to overeating while under alcohol's acute effects. While neuroimaging of chemosensory brain networks is a major field of inquiry, testing how such sensory cues are differentially processed in lean and obese subjects has only recently begun. Further, there are no studies of how alcohol exposure alters the brain response to food odors, or how its disinhibiting qualities could facilitate overeating. Knowing the brain loci that respond to such appetitive stimuli, and how they are modified by body fat and alcohol exposure, will provide critical insights about the neural systems that underlie loss of control of eating. Our preliminary data suggest that when smelling food odors, obese subjects show a greater blood oxygen level-dependent (BOLD) response than lean subjects in the insula and hippocampus. Therefore, the main hypotheses of this proposal are that: A) Lean and obese subjects have different limbic responses to the olfactory cues that enhance motivation to eat, and B) Acute alcohol intoxication i) potentiates the brain's reward system response to food odors, and ii) affects brain systems involved in behavioral inhibition and eating restraint. To test these hypotheses, we have modified functional magnetic resonance imaging (fMRI) paradigms successfully used to study alcoholic drink aromas in subjects at risk for alcoholism and in ongoing work of inhibitory control under alcohol exposure. Our specific aims are to: 1) Determine the effect of adiposity on food aroma-induced responses of specific limbic-frontal (orbitofrontal cortex, medial frontal cortex, amygdala, hippocampus, and insula) areas, 2) Examine the relationships between caloric intake and food aroma-induced responses, and 3) Study the "apiritif" effect on the response to food odors. The studies in this proposal are particularly novel because, unlike prior neuroimaging research of obesity or food-cue responsiveness, we will relate the reward system response to food cues to real world conditions, including: 1) Subjects' eating behavior at realistic meal intervals that do not disrupt or interfere with circadian rhythms, 2) The effect of a meaningful reduction in calories on brain responses to food cues (as would be experienced under dieting conditions), and 3) The effect of alcohol as consumed before meals on the brain response to food cues, inhibition, and eating behavior. To accomplish these aims we will also use food aromas, which are particularly salient stimuli that convey a more immediate presence of reward than do food images.

描述（由申请人提供）：食物香气​​是强烈的食欲线索，是食物风味和享乐品质所固有的，并且此类线索可能会导致暴饮暴食。饮酒同样会“引发”食欲，并在酒精的急性作用下导致暴饮暴食。虽然化学感觉大脑网络的神经成像是一个主要的研究领域，但测试这些感觉线索在瘦人和肥胖受试者中如何进行差异化处理的测试最近才开始。此外，目前还没有研究表明酒精暴露如何改变大脑对食物气味的反应，或者酒精的去抑制特性如何导致暴饮暴食。了解对此类食欲刺激做出反应的大脑位点，以及它们如何被身体脂肪和酒精暴露所改变，将为我们提供有关导致饮食失控的神经系统的重要见解。我们的初步数据表明，当闻到食物气味时，肥胖受试者的岛叶和海马体表现出比瘦受试者更大的血氧水平依赖性（BOLD）反应。因此，该提案的主要假设是：A) 瘦和肥胖受试者对增强进食动机的嗅觉线索有不同的边缘系统反应，以及 B) 急性酒精中毒 i) 增强大脑奖励系统对食物气味的反应，并且ii) 影响涉及行为抑制和饮食限制的大脑系统。为了检验这些假设，我们修改了功能磁共振成像（fMRI）范式，成功用于研究有酗酒风险的受试者的酒精饮料香气以及正在进行的酒精暴露下的抑制控制工作。我们的具体目标是：1) 确定肥胖对特定边缘额叶（眶额皮层、内侧额叶皮层、杏仁核、海马体和岛叶）区域由食物香气引起的反应的影响，2) 检查热量摄入与热量摄入之间的关系。食品香气引起的反应，3) 研究“apiritif”对食品气味反应的影响。本提案中的研究特别新颖，因为与之前关于肥胖或食物提示反应的神经影像学研究不同，我们会将奖励系统对食物提示的反应与现实世界的条件联系起来，包括：1）受试者在现实的进餐时间间隔内的饮食行为不扰乱或干扰昼夜节律，2) 有意义地减少卡路里对大脑对食物线索的反应的影响（如在节食条件下所经历的），以及 3) 饭前饮酒对大脑反应的影响到食物暗示、抑制和饮食行为。为了实现这些目标，我们还将使用食物香气，它们是特别显着的刺激物，比食物图像更能立即传达奖励的存在。