Neurobehavioral Assessment of Reward Sensitivity in Young Smokers

 描述（由申请人提供）：有几个因素导致尼古丁依赖，但奖励敏感性背后的大脑回路失调起着根本作用。人们认为，长期吸毒会导致人们以牺牲自然回报为代价，将过多的动机价值归因于毒品。调节对自然奖励的敏感性降低的神经生物学过程仍然不清楚。我们不知道年轻吸烟者的大脑奖赏敏感性差异是否已经存在，或者这些差异是否只在长期使用尼古丁后才会出现。此外，我们还不知道大脑奖励敏感性差异如何与享乐能力的行为和主观测量相关（即，不喜欢快乐的活动）。本申请的目的是评估使用新发现的神经生物标志物来表征青少年奖励敏感性的个体差异的可行性。我们的中心假设是，年轻的吸烟者已经表现出对自然奖励的迟钝的大脑反应，这些差异将与享乐能力的行为和自我报告措施相关。为了验证这一假设，我们将使用密集阵列事件相关电位（ERP），行为和自我报告措施来评估年轻吸烟者和从不吸烟者的奖励敏感性。这种多模态方法将使我们能够将享乐能力的主观和行为变化与其神经基础联系起来。我们将通过以下具体目标来实现我们的目标：1）描述年轻吸烟者大脑奖励敏感性的行为相关性; 2）确定尼古丁对年轻人奖励敏感性的作用。我们的方法是创新的，因为这里提出的多模态评估将使我们能够调查奖励处理结构的神经生物学，行为和主观领域之间存在的关系，并确定尼古丁如何改变年轻吸烟者。确定青少年的神经，行为和奖励敏感性的主观措施是如何相互关联的是重要的，因为它是必要的初步步骤，以了解如何在享乐能力的个体差异赋予尼古丁依赖的脆弱性。该项目的成果将有助于为高危人群制定新的、有效的循证预防战略，并有助于制定更成功的干预措施，以促进已经成瘾的人戒烟。

 DESCRIPTION (provided by applicant): Several factors contribute to nicotine dependence, but dysregulation of brain circuits underlying reward sensitivity play a fundamental role. Chronic drug use is thought to result in the attribution of excessive motivational value to drugs at the expense of natural rewards. The neurobiological processes mediating reduced sensitivity to natural rewards are still obscure. We do not know whether brain reward sensitivity differences are already present in young smokers or whether these differences develop only after long-term nicotine use. Furthermore, we do not yet know how brain reward sensitivity differences are related to behavioral and subjective measures of hedonic capacity (i.e., the tendency to not enjoy pleasurable activities). The objective of this application is to assess the feasibility of usng a newly discovered neural biomarker to characterize youths' individual differences in reward sensitivity. Our central hypothesis is that young smokers will already show blunted brain responses to natural rewards and that these differences will correlate with behavioral and self- report measures of hedonic capacity. To test this hypothesis we will assess reward sensitivity in young smokers and never smokers using dense array event-related potentials (ERPs), behavioral, and self-report measures. This multi-modal approach will allow us to link subjective and behavioral variation in hedonic capacity to its neural underpinnings. We will achieve our objective by pursuing the following Specific Aims: 1) Characterize in young smokers the behavioral correlates of brain reward sensitivity; 2) Determine the role exerted by nicotine on youths' reward sensitivity. Our approach is innovative because the multimodal assessment proposed here will allow us to investigate the relationships existing among neurobiological, behavioral, and subjective domains of the reward-processing construct and to determine how nicotine alters them in young smokers. Determining in youths how neural, behavioral, and subjective measures of reward sensitivity interrelate is significant because it is the necessary preliminary step to understanding how individual differences in hedonic capacity confer vulnerability to nicotine dependence. The results of this project will contribute to the development of new and effective evidence-based prevention strategies for individuals at risk, and to the creation of more successful interventions to promote abstinence in individuals already addicted.