Effects on Caffeine on Adolescent Behavior and Physiology

描述（由申请人提供）：美国人每年消耗超过150亿加仑的苏打水；相当于每人550罐。在过去的30年里，青少年中咖啡因的使用量增加了70%。在这个年龄段，最受欢迎的咖啡因摄入方式是苏打水。除了咖啡因的潜在健康风险外，苏打水往往含有高水平的糖，这会使儿童面临患龋齿和超重的风险。虽然目前还不清楚咖啡因本身是否会上瘾，但成年和青少年咖啡因使用者的一小部分符合精神疾病诊断与统计手册- iv的药物依赖标准。此外，咖啡因的使用会增加对可卡因、安非他命和尼古丁的敏感性和依赖性。因为糖是一种已知的“自然奖励”，它激活了与滥用药物相似的神经通路，我们假设咖啡因和糖的长期配对会导致糖的消耗增加，可能是通过增加含有添加糖的食物和饮料的强化价值来调节的。这里概述的研究将验证这一假设，并确定青少年是否对咖啡因的影响产生生理和/或心理上的耐受性。12-17岁的儿童将根据他们自我报告的每日咖啡因摄入量被细分为四分之一。这将使我们能够评估是否有不同程度的习惯性咖啡因摄入会导致对咖啡因摄入的生理和行为反应的变化。在Specific Aim 1中，剂量反应研究将通过对安慰剂和三剂量咖啡因的服用进行生理（心率、血压和手颤）和心理测量来进行。此外，咖啡因对食用含添加糖的食品和饮料的影响以及对蔗糖的敏感性和喜爱程度也将被评估。具体目标2将测量慢性和急性咖啡因如何调节对新饮料的口味偏好。最后，具体目标3将评估含咖啡因和不含咖啡因饮料的相对强化价值。这些研究调查了一系列关于青少年摄入咖啡因的生理和行为后果的新问题。此外，这些结果将为咖啡因的使用与食物偏好之间的潜在联系提供信息，特别是对添加糖含量高的食物和饮料的偏好。获得NIH资助并完成这组研究将通过提供人类摄取行为、行为药理学和成瘾领域的培训，为首席研究员的职业目标做出贡献。这些研究是建立一条独立研究路线的第一步，该研究涉及研究调节摄食行为的神经元机制。此外，该奖项将展示成为独立研究者和竞争R01拨款所需的资金潜力。

DESCRIPTION (provided by applicant): Americans consume over 15 billion gallons of soda per year; the equivalent of >550 cans per individual. Caffeine use in adolescents has increased by 70% in the past 30 years. Within this age group, the most popular route of caffeine administration is soda. In addition to potential health risks from consuming caffeine, soda tends to contain high levels of sugar, which puts children at risk for dental caries and overweight. Although it is unclear if caffeine itself is addictive, a subset of adult and adolescent caffeine users meet the Diagnostic and Statistical Manual for Mental Disorders-IV criteria for drug dependence. In addition, caffeine usage increases sensitivity and potentiates addiction to cocaine, amphetamine, and nicotine. Because sugar is a known "natural reward" that activates similar neuronal pathways as drugs of abuse, we hypothesize that the long-term pairing of caffeine with sugar leads to enhanced sugar consumption, potentially mediated by increased reinforcing value of foods and beverages containing added sugar. The studies outlined here will test this hypothesis as well as determine whether adolescents develop physiological and/or psychological tolerance to the effects of caffeine. Children ages 12-17 years will be subdivided into quartiles based on their self-reported daily caffeine intake. This will allow us to assess whether there are different levels of habitual caffeine use lead to changes in physiological and behavioral responses to caffeine administration. In Specific Aim 1, a dose response study will be conducted by taking physiological (heart rate, blood pressure, and hand tremor) and psychological measurements in response to administration of placebo and three doses of caffeine. In addition, the effects of caffeine on consumption of foods and beverages containing added sugar and sensitivity to and liking of sucrose will also be assessed. Specific Aim 2 will measure how chronic and acute caffeine modulates taste preferences for novel drinks. Finally, Specific Aim 3 will assess the relative reinforcing value of caffeinated and non-caffeinated beverages. These studies investigate a novel set of questions concerning the physiological and behavioral consequences of caffeine ingestion among adolescents. In addition, these results will provide information on the potential link between caffeine use and the development of food preferences, in particular preference for foods and beverage with high levels of added sugar. Obtaining NIH funding and completing this set of studies will contribute to the Principal Investigator's career goals by providing training in the areas of human ingestive behavior, behavioral pharmacology, and addiction. These studies are a first step toward establishing an independent line of research that involves studying neuronal mechanisms that regulate ingestive behavior. In addition, this award will demonstrate the funding potential necessary to become an independent investigator and to compete for an R01 grant.