Behavioral and Neural Consequences of Sleep Loss on Adolescent Affective Function

描述(申请人提供)：睡眠不足在青春期非常普遍。青春期睡眠受限的原因是大脑/行为/社会环境在睡眠-觉醒过程中的相互作用和昼夜节律的结果。青春期的生理变化造成了一种自然的倾向，即喜欢熬夜，也会增加困倦。然而，关键的睡眠行为(熬夜和反复无常的睡眠/起床时间表)在很大程度上是这些生物倾向和社会环境(即，人造光的影响，刺激社交媒体，如短信和互联网，以及其他高回报活动结合早期开学时间的影响)之间的相互作用。此外，在生理、社交和情感发育发生关键成熟变化的时候，这些相互作用正在合谋剥夺年轻人的睡眠。青春期的睡眠障碍可能会引发奖赏和情绪处理受损；情感和行为失调；进一步的睡眠问题；最终导致临床抑郁和药物滥用的负面级联反应。这项研究的主要目标是阐明潜在的生物心理社会机制，将睡眠问题与青春期抑郁和药物滥用的发展联系起来。了解睡眠不足导致青春期情感功能障碍以及行为和心理健康问题的易感性的机制，可以为开发更有效的早期干预措施提供杠杆，包括针对社会环境的临床和社会政策层面的努力(即学校开学时间、父母和青少年教育计划以及行为干预)。作为解决这一目标的第一步，拟议的研究将评估对睡眠时间和社会背景进行良好控制的实验室操作对支持奖励和情绪调节的神经系统活动的影响，以及对相关情感行为的影响。我们的具体目标是：(1)调查短暂睡眠限制和同伴社会背景对奖励和冒险的影响；(2)调查短暂睡眠限制和同伴社会背景对情绪反应/调节的影响。采用受试者内交叉设计，对青春期中期青年在两种实验条件下进行研究：(1)睡眠限制(两晚上床4小时)和(2)延长睡眠(两晚上床10小时)。多导睡眠监测的睡眠状况将在第二天进行功能磁共振成像(FMRI)和行为测试。我们将使用有效的奖赏和情绪处理神经成像任务来检查皮层-皮质下激活对食欲和厌恶刺激的反应。参与者将进行成对的朋友研究，使我们能够检查同伴社会环境对情感功能的影响。我们还将检查神经和行为对社会相关刺激的反应。

DESCRIPTION (provided by applicant): Sleep loss is extremely prevalent during adolescence. The causes of sleep restriction in adolescence are the result of brain/behavior/social context interactions in sleep-wake and circadian regulation. Biological changes at puberty create a natural tendency to prefer staying up late as well as increased sleepiness. However the key sleep behaviors (patterns of staying up late and erratic sleep/wake schedules) are largely an interaction between these biologic tendencies and the social environment (i.e., effects of artificial light, stimulating social media such as texting and the internet, and other highly rewarding activities combined with early school start times). Moreover, these interactions are conspiring to rob youth of sleep at a time of critical maturational changes in physical, social, and affective development. Sleep disruption in adolescence may initiate a negative cascade of impaired reward and emotion processing; affective and behavioral dysregulation; further sleep problems; and ultimately, clinical depression and substance abuse. The broad goal of this research is to elucidate potential biopsychosocial mechanisms linking sleep problems with the development of depression and substance abuse in adolescence. Understanding the mechanisms by which sleep loss contributes to vulnerabilities for affective dysfunction and behavioral and mental health problems triggered during adolescence can provide leverage for developing more effective early interventions, including both clinical and social policy-level efforts aimed at the social environment (i.e., school start times, parental and youth education programs, and behavioral interventions). As a first step to address this goal, the proposed study will evaluate the effects of well-controlled laboratory manipulations of sleep duration and social context on activity in neural systems supporting reward and emotion regulation, and on related affective behaviors. Our specific aims are: (1) to investigate the impact of transient sleep restriction and peer social context on reward and risk-taking; and (2) to investigate the impact of transient sleep restriction and peer social context on emotional reactivity/ regulation. Using a within-subjects crossover design, youth in middle adolescence will be studied under two experimental conditions: (1) sleep restriction (two nights of 4 hours time in bed) and (2) sleep extension (two nights of 10 hours time in bed). Polysomnographically-monitored sleep conditions will be followed by functional magnetic resonance imaging (fMRI) and behavioral testing the next day. We will employ validated reward and emotion processing neuroimaging tasks to examine cortical-subcortical activation in response to appetitive and aversive stimuli. Participants will be studied in pairs of friends, enabling us to examine the influence of the peer social context on affective functioning. We will also examine neural and behavioral responses to socially- relevant stimuli.