Neurobehavioral Determinants of Adolescent Substance Use and HIV/STD Behaviors

描述(由申请人提供)：青春期的特点是更容易受到危害健康的行为的影响，如吸毒和酗酒以及从事不安全的性行为，这些行为一起是吸毒和性传播疾病(包括人类免疫缺陷病毒(HIV)感染)的主要近因。发展神经科学的研究表明，青春期的冒险行为可能源于两个不同神经系统的不同发展轨迹，这两个神经系统调节高风险的决定：(I)奖励系统过早成熟，使决策偏向高回报选项，以及(Ii)认知控制系统较晚成熟，使决策偏离具有潜在负面后果的选项。然而，我们对发展中的奖赏和控制神经系统如何相互作用，以产生对导致不利健康后果的糟糕决策的不同脆弱性知之甚少。我们提出了第一个纵向分析，以考察个体在报酬/风险敏感性和认知控制的发展轨迹上的差异如何与青少年物质使用和危险性行为的发展有关。我们将研究来自阿巴拉契亚未充分研究社区的120名青少年在整个青春期中期(13-17岁)期间使用药物(例如，吸烟、酒精、大麻和其他非法药物使用)和与艾滋病毒/性传播疾病相关的危险性行为(例如，多个性伴侣和无保护的性行为)的后果。我们将使用功能磁共振成像(FMRI)来识别风险决策的神经关联：奖励/风险敏感性(奖励系统)和认知控制(控制系统)。我们将在神经水平上以及在行为标准评估(例如执行功能任务)和自我和父母报告的属性(例如接近/回避)的背景下检验我们的假设，以获得对奖励和控制系统与青少年冒险行为之间的联系的更全面的理解。基于我们的概念模型，我们将检验认知控制是否在统计上缓和了奖励/风险敏感性对青少年物质使用和HIV/STD相关危险性行为的影响。我们假设，过度活跃的奖赏敏感性和低活跃的风险敏感性的神经模式将与更多地参与物质使用和危险的性行为有关，特别是对于那些认知控制不足的青少年。这项拟议的研究将通过提供关于奖励和控制神经系统之间相互作用的新知识来做出理论贡献，据我们所知，这些知识还没有被研究过。我们的设计还将使我们能够研究青少年危险行为和这些神经过程之间的相互作用。这项工作的发现将产生关键信息，用于识别具有高度神经生物学易感性的青少年，以发展药物滥用和危险的性行为，并将有可能改善预防工作，积极改变处于药物成瘾和艾滋病毒/性传播疾病风险的青少年的发展途径。

DESCRIPTION (provided by applicant): Adolescence is characterized by heightened vulnerability to health risk behaviors such as experimenting with drugs and alcohol and engaging in unsafe sexual activity that together are the major proximal causes of drug addiction and sexually transmitted diseases (STDs) including human immunodeficiency virus (HIV) infection. Research in developmental neuroscience suggests that risk-taking in adolescence may derive from differing developmental trajectories of two distinct neural systems that regulate risky decisions: (i) early maturation of a reward system that biases decisions toward high-reward options, combined with (ii) late maturation of a cognitive control system that biases decisions away from options with potential negative consequences. Yet, we know very little about how developing reward and control neural systems interact to produce differential vulnerability to poor decision-making that leads to adverse health outcomes. We propose the first longitudinal analyses to examine how individual differences in developmental trajectories of reward/risk sensitivity and cognitive control are related to the development of adolescent substance use and risky sexual behaviors. We will study a sample of 120 adolescents from understudied Appalachian communities for the outcomes of substance use (e.g., tobacco, alcohol, marijuana, and other illicit drug use) and HIV/STD-related risky sexual behaviors (e.g., multiple sexual partners and unprotected sex) throughout middle adolescence (13-17 years). We will use functional magnetic resonance imaging (fMRI) to identify neural correlates of risky decision- making: reward/risk sensitivity (reward system) and cognitive control (control system). We will examine our hypotheses at the neural level as well as within the context of standard assessments of behavior (e.g., executive function tasks) and self- and parent reported attributes (e.g., approach/avoidance) to obtain a more integrated understanding of the connections between reward and control systems and adolescent risk-taking. Based on our conceptual model we will test whether cognitive control statistically moderates the effects of reward/risk sensitivity on adolescent substance use and HIV/STD-related risky sexual behaviors. We hypothesize that neural patterns of hyperactive reward sensitivity and hypoactive risk sensitivity will be related to greater involvement in substance use and risky sexual behaviors, especially for those adolescents with hypoactive cognitive control. The proposed research will make theoretical contributions by providing new knowledge about the interaction between reward and control neural systems that, to our knowledge, have not been studied. Our design will also allow us to investigate the reciprocal interplay between adolescent risky behaviors and these neural processes. The findings from this work will yield critical information for identifying adolescents with high neurobiological vulnerability for developing substance abuse and risky sexual behaviors and will have the potential to improve prevention efforts to positively alter developmental pathways of youth who are at risk for drug addiction and HIV/STDs.