Reward Processing in Adolescence

描述（由申请人提供）：奖励处理是决策的重要组成部分，对冒险行为、情绪障碍和药物滥用有影响。青春期是冒险行为达到顶峰、情绪障碍和药物滥用可能出现的发展时期。对于奖励和惩罚如何改变青少年的行为，我们还没有一个清晰的认识。我们对奖励/惩罚如何影响大脑回路的理解就更少了，而大脑回路是在这个发育阶段被招募来做决定的。我们建议研究120名10至20岁的健康受试者，采用纵向/横断面混合设计，跨越10年的发展。我们将以眼动作为模型系统，评估与金钱激励对抑制任务不适当反应能力的影响相关的发展变化。利用功能磁共振成像，我们将研究支持奖励/惩罚处理的额纹状体回路招募的发育变化，并描述这些变化如何影响支持认知控制的已知机制。扩散张量成像（DTI）将用于评估髓鞘形成对观察到的额纹状体回路募集变化和随后的发育行为变化的贡献。这些结果与年龄、青春期状态、性别和感觉寻求指数之间的关系将被调查，以解释发育轨迹的个体差异。这项工作将产生一个青春期奖励/惩罚过程成熟的规范模板，这是理解青少年大脑在冒险行为、情绪障碍和药物滥用方面的脆弱性的关键一步。公共卫生相关性：青春期是冒险行为（药物滥用、无保护的性行为、极限运动）增加的时期，这导致了惊人的高死亡率。此外，大多数主要的精神疾病出现在从青春期到成年期的过渡时期。我们提出的研究可以通过提供有关青少年大脑处理的局限性和脆弱性以及这些如何影响奖励评估和决策的信息来为这些文献提供信息。

DESCRIPTION (provided by applicant): Reward processing is a crucial component of decision making and has implications for risk taking behavior, mood disorders, and substance abuse. Adolescence is a period of development when risk taking behavior peaks and mood disorders and substance abuse can emerge. We do not yet have a clear understanding of how reward and punishment alter behavior in adolescence. We have even less of an understanding of how reward/punishment influences the brain circuitry that is recruited to make decisions at this developmental stage. We propose to study 120 ten to 20 year-old healthy subjects in a hybrid longitudinal/cross-sectional design that spans ten years of development. We will assess the developmental changes related to the effects of monetary incentives on the ability to suppress task inappropriate responses, using eye movements as a model system. Using fMRI, we will investigate developmental changes in the recruitment of frontostriatal circuitry supporting reward/punishment processing and characterize how these affect known mechanisms supporting cognitive control. Diffusion Tensor Imaging (DTI) will be used to assess the contribution of myelination to observed changes in the recruitment of frontostriatal circuitry and subsequent behavioral changes with development. Associations between these results and age, pubertal status, gender, and sensation seeking indices will be investigated to account for individual variability in developmental trajectories. This work will result in a normative template of the maturation of reward/punishment processes through adolescence, a critical step toward understanding vulnerabilities in the adolescent brain for risk taking behavior, mood disorders, and substance abuse. PUBLIC HEALTH RELEVANCE: Adolescence is a period marked by an increase in risk-taking behavior (substance abuse, unprotected sex, extreme sports) that has lead to a strikingly high mortality rate. Additionally, most major psychiatric illnesses emerge during the period of transition from adolescence to adulthood. We propose studies that can inform these literatures by providing information regarding the limitations and vulnerabilities in brain processing present in adolescence and how these affect reward assessment and decision making.