Contribution of dopamine to risk attitude across the lifespan

描述（由申请人提供）：在我们的社会中，个人需要通过整合大量可获得的信息来做出复杂的经济选择，这些选择往往具有不确定的结果。人生各个阶段对决策的日常需求，加上社会中最年轻和最年长的成员寿命的延长和获取信息的机会的增加，使得评估不同年龄组之间决策的潜在差异成为一个关键的研究领域。在具有确定和不确定结果的竞争选项中进行有利选择是个人对奖励结果的主观评估和基于预测信息准确估计这些结果所需的强化学习过程的产物。因此，结合主观评价和强化学习中年龄相关差异的风险决策神经经济学框架，为深入了解整个生命周期中选择行为的潜在基础提供了有力的工具。本研究的主要目标是建立风险下决策的行为和神经生物学特征，并研究主观奖励评估和强化学习在不同生命阶段对这些特征的贡献。我们假设，从青春期到成年期和衰老期多巴胺信号的发育/成熟变化是决策机制中这些基本成分的年龄特异性编码对选择行为的基本贡献。我们提出了三个特定的目的来研究青春期、成年和老年大鼠在概率决策、强化学习和主观奖励评估过程中腹侧纹状体中的多巴胺信号。

DESCRIPTION (provided by applicant): Individuals in our society are required to make complex economic choices, often with uncertain outcomes, by integrating large amounts of information available to inform those choices. This daily requirement for decision making at all stages of life, together with increasing life spans and a growing accessibility to information among the youngest and eldest members of society, makes an evaluation of potential differences in decision making across age groups a critical area of research. Choosing advantageously among competing options with certain and uncertain outcomes is a product of individual subjective valuation of rewarding outcomes and the reinforcement learning processes required for accurately estimating those outcomes based on predictive information. Accordingly, a neuroeconomic framework of decision making under risk incorporating the contribution of age-related distinctions in subjective valuation and reinforcement learning provides a powerful tool for insight into the underlying substrates of choice behavior across the lifespan. The primary goal of the proposed work is to establish behavioral and neurobiological profiles of decision making under risk across the lifespan and examine the contribution of subjective reward valuation and reinforcement learning to these profiles at different life stages. We hypothesize that developmental/maturational changes in dopamine signaling from adolescence through adulthood and senescence is a fundamental contributor to choice behavior through the age-specific encoding of these essential components to the decision-making apparatus. We propose three specific aims examining dopamine signaling in the ventral striatum during probabilistic decision making, reinforcement learning, and subjective reward valuation in adolescent, adult, and aged rats.