Interactions Between Nicotine Addiction and Food Reward

描述(由申请人提供)：戒烟后体重经常增加(2)。对体重增加的恐惧被认为是不戒烟的关键原因(3)，而实际体重增加是复发的主要原因，尤其是在女性中(6)。虽然戒烟后体重增加的原因很复杂(2)，但卡路里摄入量增加被认为是主要来源之一(2，7，8)。就像接触吸烟线索会导致吸烟一样，暴露在食物线索中也会诱发进食，即使是在吃饱了的动物身上也是如此。卡路里摄入量增加的一种解释是，食物和香烟的奖励存在共同的神经机制，尼古丁成瘾会导致大脑对吸烟线索的编码发生变化，也会导致大脑对食物线索的编码发生变化。这个应用程序的目标是验证这一预测。我们建议使用功能磁共振成像来测试这样的预测，即尼古丁成瘾与对食物提示的边缘反应减少有关，而戒烟会导致对食物提示的边缘反应增加。根据药物成瘾的激励敏感化理论(13，14)，我们还预测食物奖励的神经编码的差异是食物线索的激励显著编码所特有的，而不是表现为对食物接收的知觉或神经反应的差异。为了评估这些预测，我们将检查吸烟者、非吸烟者和戒烟者对食物气味、同样令人愉快和强烈的花香、食物接收和无味溶液接收的大脑反应。为了补充神经成像数据，我们还计划收集食物奖励的感知和行为测量，包括1)对食物和花香的享乐评级的评估，以及食物接收；2)评估受试者将为食物奖励工作的数量；以及3)临时消费巧克力曲奇。然后，对这些指标的反应将被用作协变量，以预测吸烟者、非吸烟者和严重缺乏吸烟者对食物香味的神经反应。如果数据支持我们的预测，那么我们将使用它来支持R01应用程序，以测试大脑和对食物的行为反应是否可以用来预测戒烟期间的体重增加。如果大脑反应确实能预测体重增加，那么我们就已经开发出一种方法来识别有复发风险的个人，以便他们能够成为进一步治疗干预的目标。

DESCRIPTION (provided by applicant): Weight gain frequently follows smoking cessation(2). Fear of weight gain is cited as a key reason not to quit(3) and actual weight gain is a primary reason for relapse, especially among women(6). Although the causes of weight gain following smoking cessation are complex(2), increased caloric intake is recognized as one of the primary sources(2,7,8). Just as exposure to smoking cues can induce smoking, exposure to food cues can induce feeding, even in sated animals(9). One explanation for increased caloric intake is that there are common neural mechanisms for food and cigarette reward and that nicotine addiction, which results in changes in brain encoding of smoking cues, also results in changes in brain encoding of food cues. The goal of this application is to test this prediction. We propose to use fMRI to test the prediction that nicotine addiction is associated with a decrease in the limbic response to food cues whereas cessation results in an increase in the limbic response to food cues. In accordance with the incentive-sensitization theory of drug addiction(13,14) we also predict that differences in neural encoding of food reward is specific to incentive salience encoding of food cues and is not characterized by differences in perceptual or neural response to food receipt. To evaluate these predictions we will examine brain response to food odors, equally pleasant and intense floral odors, food receipt, and receipt of a tasteless solution in smokers, non-smokers, and acutely abstinent smokers. To compliment the neuroimaging data we also plan to gather perceptual and behavioral measures of food reward including 1) assessment of hedonic ratings of food and floral odors, and food receipt; 2) assessment of the amount a subject will work for a food reward; and 3) ad lib consumption of chocolate chip cookies. Responses on these measures will then be used as covariates to predict neural response to food aromas in smokers, nonsmokers and acutely deprived smokers. If the data support our predictions then we will use it to support an R01 application to test whether brain and behavioral response to food can be used to predict weight gain during smoking cessation. If brain response does predict weight gain then we will have developed a method to identify individuals at risk for relapse so that they can be targeted for further therapeutic intervention.