Neural Basis of Decisions about Uncertain Rewards

不确定奖励决策的神经基础

• 批准号: 7570308
• 负责人: Jamie D. Roitman
• 金额: $ 7.85万
• 依托单位: UNIVERSITY OF ILLINOIS AT CHICAGO
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-09-30 至 2009-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7570308
• 关键词: Alcohols; Area; Behavior; Behavioral; Choice Behavior; Clinical; Cocaine; Costs and Benefits; Cues; Decision Making; Drug Addiction; Evaluation; Event; Fatty acid glycerol esters; Food; Future; Gambling; Goals; Health; Health financing; Illicit Drugs; Impulsive Behavior; Individual; Intake; Lead; Legal; Measures; Neurons; Nicotine; Nucleus Accumbens; Numbers; Obesity; Outcome; Outcome Assessment; Pattern; Pharmaceutical Preparations; Play; Population; Process; Public Health; Rattus; Recording of previous events; Rewards; Risk; Risk Behaviors; Risk-Taking; Role; Safety; Sampling; Signal Transduction; Societies; Structure; Sucrose; Testing; Thinking; Training; addiction; base; cost; drug relapse; neural circuit; preference; relating to nervous system; response; reward processing; stem; willingness

DESCRIPTION (provided by applicant): The willingness to engage in risky behaviors is hallmark of drug addiction, gambling, and obesity. Presumably, one chooses to administer an illicit drug, over-consume a fat-laden meal, or put $1000 on red because the immediate outcome of the choice is potentially rewarding. The goal of this proposal is to identify patterns of activity in neural structures involved in evaluating rewards and making decisions between certain and risky outcomes that will inform how risk-preference is represented in the activity of single neurons. Rats will be trained to perform a Risk task, in which they choose between two levers in a test chamber that lead to different reward outcomes (sucrose pellets). Pressing the Certain lever always earns a Small reward, and pressing the Uncertain lever will either pay a Large reward or Omit the reward. Large or Omitted reward outcome is chosen randomly, so that subjects cannot track the number of Large outcomes to maximize overall payoffs across trials. In a forced response block, each lever will be presented alone on alternate trials, which provides the opportunity for the rat to equally sample both behavioral options and their associated consequences. This is followed by a free choice block, in which both levers are presented simultaneously and rats are able to select one. Analyses of choices will focus on risk-preference across sessions and the influence of reward-history on upcoming choices. While rats perform the Risk task we will record the electrophysiological activity of single neurons in the Nucleus Accumbens (NAc), which is critical for reward processing and in the Orbitofrontal cortex (OFC), an area thought to be important for making decisions based on reward outcome. In both NAc and OFC, we will measure responses to events leading up to, during, and following reward delivery or omission. The level of neural activity will be compared across the two behavioral responses (Certain-Uncertain), when freely chosen or not, and to the three possible outcomes (Small, Large, Omit). The long-term goal of our studies is to determine how aberrant signaling in these areas may underlie inaccurate representations of reward which may in turn lead to over-valuation of risky behaviors. PUBLIC HEALTH RELEVANCE: The pervasive problems associated with drug addiction, gambling, or overconsumption (of food or goods) stem from a willingness to engage in behaviors that yield risky outcomes. The goal of this project is to identify patterns of activity in neural structures involved in evaluating rewards and making decisions about choices with risky consequences that will inform how risk-preference is represented in the activity of single neurons. These studies have the potential to identify mechanisms of risk-prone behaviors and therefore new targets for their treatment.

描述（由申请人提供）：愿意从事危险行为是吸毒、赌博和肥胖的标志。据推测，一个人选择服用非法药物，过量食用一顿高脂肪的饭，或者把1000美元押在红色上，因为这种选择的直接结果可能是有益的。这一提议的目标是识别参与评估奖励和在确定和有风险的结果之间做出决定的神经结构的活动模式，这将告知风险偏好如何在单个神经元的活动中表现出来。老鼠将被训练去执行一个风险任务，在这个任务中，他们在一个实验室内的两个杠杆之间做出选择，这两个杠杆会导致不同的奖励结果（蔗糖颗粒）。按下特定的杠杆总是会获得小奖励，而按下不确定的杠杆要么会获得大奖励，要么会忽略奖励。大奖励或忽略奖励结果是随机选择的，因此受试者无法跟踪大奖励结果的数量，从而在整个试验中最大化总体回报。在强制反应区，每个杠杆将单独出现在交替的试验中，这为大鼠提供了平等地抽样行为选择及其相关后果的机会。接下来是一个自由选择模块，在这个模块中，两个杠杆同时出现，老鼠可以选择一个。对选择的分析将侧重于风险偏好和奖励历史对即将到来的选择的影响。当大鼠执行风险任务时，我们将记录伏隔核（NAc）和眶额皮质（OFC）中单个神经元的电生理活动，这两个区域对奖励处理至关重要，而眶额皮质被认为是基于奖励结果做出决定的重要区域。在NAc和OFC中，我们将测量对奖励交付或遗漏之前、期间和之后事件的反应。神经活动水平将在两种行为反应（确定-不确定）之间进行比较，当自由选择或非自由选择时，以及三种可能的结果（小，大，省略）。我们研究的长期目标是确定这些区域的异常信号如何可能导致对奖励的不准确表征，从而导致对风险行为的高估。公共卫生相关性：与吸毒成瘾、赌博或（食物或商品）过度消费有关的普遍问题源于愿意从事产生危险结果的行为。这个项目的目标是识别神经结构的活动模式，这些活动模式涉及到评估奖励和对有风险后果的选择做出决定，这将告知风险偏好如何在单个神经元的活动中表现出来。这些研究有可能确定风险倾向行为的机制，从而为其治疗提供新的目标。