Delay Discounting and the Choice to Take a Drug

延迟折扣和服用药物的选择

• 批准号: 8144842
• 负责人: William L. Woolverton
• 金额: $ 29万
• 依托单位: UNIVERSITY OF MISSISSIPPI MED CTR
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-09-30 至 2015-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8144842
• 关键词: Affect; Attention; Behavior; Behavioral; Cocaine; Dose; Drug abuse; Food; Goals; Human; Injection of therapeutic agent; Literature; Modeling; Monkeys; Nature; Outcome; Pharmaceutical Preparations; Psychological reinforcement; Relative (related person); Research; Rewards; Saccharin; Self Administration; Sucrose; Therapeutic; Time; Work; base; design; discount; discounting; drug abstinence; drug abuser; drug of abuse; human subject; interest; non-drug; public health relevance; reinforcer; research study; response

DESCRIPTION (provided by applicant): Delay between a behavior and its reinforcer usually decreases the subjective value of the reinforcer, a phenomenon termed delay discounting. There is a well-established quantitative model, the hyperbolic discounting function, which describes delay discounting. Research with delay discounting has made substantial theoretical contributions to our understanding of drug abuse. For example, drug abusers discount the value of drugs more rapidly than they do monetary reinforcers, suggesting that discounting rate may depend on the nature of the reinforcer. However, experiments comparing discounting of drugs and money have studied a single magnitude of each reinforcer in a hypothetical choice situation. In humans, magnitude of a delayed reinforcer is a crucial determinant of discounting rate. Research with non-humans is beginning to contribute to our understanding of the effects of delay on drug choice. Recently, we found that monkeys discounted non-drug reinforcers more steeply than they did cocaine, a result opposite to that observed in drug abusers. This difference may be due to the nature of the specific reinforcers studied, or to the use of real reinforcers with monkeys vs. hypothetical reinforcers with humans. Alternatively, it may be a consequence of differences in the relative magnitudes of the reinforcers. We propose to investigate the effect of reinforcer magnitude and delay on the rate of discounting of drug and non-drug reinforcers in monkeys given allomorphic (i.e., drug/non-drug) choices. Aim 1 is to establish dose-response functions for cocaine when the choice is between an immediate injection of cocaine and the delayed presentation of food. Discounting functions will be established for different amounts of food available with various delays. This allomorphic choice situation (i.e., immediate drug vs. delayed food) is analogous to the one underlying discounting interpretations of drug abuse: drug abusers are assumed to impulsively choose immediate drug reinforcers over larger, delayed non-drug reinforcers. Such allomorphic choice has received little study to date. Aim 2 is to establish magnitude-response functions for food when the choice is between the presentation of an immediate amount of food and a delayed injection of cocaine. Discounting functions will be established for different doses of cocaine available with various delays. This allomorphic choice situation is important because drug abuse also can involve choosing between more immediate non-drug reinforcers and delayed drug reinforcers, as exemplified by the fact that drug abusers often devote considerable time and effort to procuring drugs. This situation has received virtually no discussion in the discounting literature. Our hypotheses for both Aims are that the discounting of the delayed reinforcer will be well described by the hyperbolic function and that rate of discounting will vary inversely with the amount of the delayed reinforcer. The results will have important implications for understanding the determinants of drug choice and, potentially, for the use of delay to reinforcement in a therapeutic context. PUBLIC HEALTH RELEVANCE: Introducing a delay between a behavior and its consequence often weakens the behavior. Drug self- administration is a strongly maintained behavior, at least partially because of its immediate effects. The present project is designed to examine the choice between a drug injection and a non-drug reward to establish the extent to which both the magnitude of reward and the delay to reward determine the outcome of that choice. The results will enhance our understanding of behavioral approaches to decreasing the choice to take a drug of abuse.

描述(由申请人提供)：行为与其增强剂之间的延迟通常会降低增强剂的主观价值，这种现象称为延迟贴现。有一个完善的量化模型，即双曲线贴现函数，它描述了延迟贴现。延迟折扣的研究为我们理解药物滥用做出了重要的理论贡献。例如，吸毒者对药物价值的折扣比货币增强剂更快，这表明折扣率可能取决于增强剂的性质。然而，比较药物折扣和金钱折扣的实验已经研究了在假设的选择情况下每种增强剂的单一数量。在人类中，延迟增强剂的大小是贴现率的关键决定因素。对非人类的研究开始有助于我们理解延迟对药物选择的影响。最近，我们发现猴子对非药物增强剂的折扣比对可卡因的折扣更大，这与在吸毒者中观察到的结果相反。这种差异可能是由于所研究的特定增强剂的性质，或者是对猴子使用真正的增强剂，而对人类使用假想的增强剂。或者，这可能是增强剂相对大小不同的结果。我们建议在猴子的同形(即药物/非药物)选择的情况下，研究增强剂的大小和延迟对药物和非药物增强剂折扣率的影响。目标1是在立即注射可卡因和延迟提供食物之间进行选择时，建立可卡因的剂量-反应函数。将为不同数量的食品建立折扣功能，但会有不同的延迟。这种同构的选择情况(即，立即药物与延迟食物)类似于对药物滥用的潜在折扣解释：吸毒者被假定冲动地选择立即药物增强剂，而不是更大的、延迟的非药物增强剂。到目前为止，这种同形选择的研究很少。目标2是在提供即刻数量的食物和延迟注射可卡因之间进行选择时，建立食物的量值反应函数。将为不同剂量的可卡因建立折扣功能，但有不同的延迟。这种同形选择的情况很重要，因为药物滥用还可能涉及在更直接的非药物增强剂和延迟的药物增强剂之间进行选择，吸毒者往往花费相当多的时间和精力购买药物就是例证。这种情况在折扣文献中几乎没有得到任何讨论。我们对这两个目标的假设都是，延迟增强剂的折扣将用双曲线函数很好地描述，并且贴现率将与延迟增强剂的数量成反比。这一结果将对理解药物选择的决定因素具有重要意义，并可能对在治疗背景下使用延迟强化治疗具有重要意义。 与公共健康相关：在行为及其后果之间引入延迟通常会削弱行为。药物自我管理是一种坚持不懈的行为，至少部分是因为它的直接影响。本项目旨在审查注射毒品和非毒品奖励之间的选择，以确定奖励的大小和延迟奖励在多大程度上决定了这一选择的结果。研究结果将增强我们对减少选择服用滥用药物的行为方法的理解。