Competing Revision: Sensitization of the Reinforcing Value of Food as a Predictor of Weight Change in Adolescents.

项目摘要：青少年的大脑被驱使去寻找强化剂，但大脑中与冲动有关的区域 控制和执行功能一直不成熟，直到成年早期。这可能会让青少年特别 容易暴饮暴食和体重增加。进食的动机，或增强食物的价值(RRV)，是一个强有力的预测因素 能量消耗和肥胖。了解导致食物RRV水平较高的因素是至关重要的 朝着开发新的肥胖症治疗和预防策略迈进。家长拨款的目的是1) 为了确定高能量密度休闲食品的RRV增加是否预测随着时间的推移体重增加2)确定 增加低能量密度零食的RRV可防止随着时间的推移体重增加3)以确定RRV是否 体力活动和/或延迟折扣(DD)缓和了食物RRV变化之间的关系 青少年的反复暴露和体重变化。我们已经完成了95%的目标基线数据收集 家长补助金中的样本以及对大约50%的目标人口的后续预约。我们有 研究表明，体重正常的儿童在重复暴露两周后，他们的零食RRV会降低，但 超重儿童多次暴露后，休闲食品的RRV未见变化。我们还表明， 反复暴露后零食的RRV增加的参与者的zBMI明显更大 与那些没有增加食物RRV的参与者相比，6个月和15个月时的变化。最后，我们展示了 基线RRV和DD高的个体在6个月和15个月时zBMI变化显著大于 食物DD和RRV低的人群。综合来看，这些发现表明，有几种行为表型 预测zBMI随时间的变化，可能有助于识别体重增加的高危个体 体重开始增加。在我们努力实现父母资助的最初目标的同时，新的想法已经 随着我们通过这项研究的进展而出现。这个相互竞争的修订提案的主要目的是构建 根据我们的初步发现，并确定1)基线行为表型的预测价值是否延伸到 青春期后期2)饮食自主性在饮食行为和体重随时间变化中的作用3)程度 其中饮食行为紊乱的发展和节食缓和基线之间的关系 行为表型和zBMI随着时间的推移而变化。这项相互竞争的修订建议将提高 通过增加额外的、适合年龄的措施，通过延长我们跟踪的时间表，来实现父母赠款的结果- 直到青春期后期和成年初期，并允许我们开发和验证一种新的饮食测量方法 在这个饮食行为的关键时期，可能特别重要的行为(饮食自主性) 发展。一旦这些因素被识别和表征，未来的研究可以集中在提炼方法上 改变食物的RRV，以此来增加健康饮食，减少不太健康的食物摄入量。

Project Summary: The adolescent brain is driven to seek out reinforcers, but the areas of the brain involved in impulse control and executive function remain immature until early adulthood. This may make adolescents particularly susceptible to overeating and weight gain. Motivation to eat, or reinforcing value (RRV) of food, is a strong predictor of energy consumption and adiposity. Understanding factors that lead to higher levels of the RRV of food is a critical first step toward developing novel treatment and prevention strategies for obesity. The purpose of the parent grant was 1) to determine if increases in the RRV of high energy density snack foods predict weight gain over time 2) to determine if increases in the RRV of low energy density snacks protect against weight gain over time 3) to determine if RRV of physical activity and/or delay discounting (DD) moderate the relationship between changes in the RRV of food after repeated exposure and weight change in adolescents. We have completed baseline data collection on 95% of our target sample in the parent grant as well as follow-up appointments on approximately 50% of our target population. We have shown that children with healthy weight decrease their RRV of snack food after two weeks of repeated exposure, but children with overweight do not show changes in RRV of snack food after repeated exposure. We have also shown that participants who showed an increase in RRV of snack food after repeated exposure had significantly greater zBMI change at 6 and 15 months compared to those participants who did not increase their RRV of food. Finally, we showed that individuals with high baseline RRV and DD had significantly greater zBMI change at 6 and 15 months compared to those with low DD and RRV of food. When taken together, these findings suggest that several behavioral phenotypes predict zBMI change over time and could potentially help to identify individuals at high risk of weight gain prior to the onset of weight gain. While we work toward completion of the original goals of the parent grant, new ideas have emerged as we have progressed through this study. The primary purpose of this competing revision proposal is to build upon our preliminary findings and determine 1) if the predictive value of baseline behavioral phenotypes extends into later adolescence 2) the role that eating autonomy plays in eating behavior and weight change over time 3) the extent to which the development of disordered eating behavior and dieting moderates the relationship between baseline behavioral phenotypes and zBMI change over time. This competing revision proposal will enhance the value of the outcomes of the parent grant by adding additional, age-appropriate measures, by extending the timeline of our follow- up to later adolescence and emerging adulthood, and by allowing us to develop and validate a novel measure of eating behavior (eating autonomy) that may be particularly important during this critical period of eating behavior development. Once these factors are identified and characterized, future studies could focus on refining methods for altering the RRV of food as a way to increase healthy eating and decrease less healthy food intake.