IMPULSIVITY--DISCOUNTING THE BENEFITS OF DRUG ABSTINENCE

吸毒可以被概念化为一种冲动的选择，因为吸毒者更喜欢吸毒的小的即时强化后果(例如，兴奋)，而不是戒毒的长时间延迟强化后果(例如，职业成功、改善的人际关系等)。几项研究表明，与非吸毒者相比，药物依赖者对延迟强化物的价值更不看好。在这些研究中，心理测量学技术被用来确定一系列大延迟奖励的主观价值(例如，在一年内交付1000美元)。这一概念模型的一个缺点是，禁欲的大延迟益处很少在一次延迟后一次性给出。相反，这些福利通常以较小的数额分几次延迟分配(例如，多年来每天都能看到的与配偶的关系略有改善)。因此，拟议研究的第一个目的是比较大延迟增强剂在一次延迟后一次性交付或在一系列延迟后以较小数量交付的情况下的折扣率。将采用2×2混合析因设计，其中诊断(药物依赖者与非吸毒者)是受试者之间的因素，而选择情况(一次性给予延迟报酬与随时间分配)是受试者之间的因素。拟议研究的第二个目的是探索延迟奖励贴现和高价奖励之间的关系。最近的几项研究表明，动物和人类对高价奖励的贴现方式类似于他们对不同价格的延迟奖励的价值进行贴现的方式(价格是指获得每一种奖励所需的努力)。将评估需求的价格弹性(对价格上涨的敏感性的衡量标准)与单个参与者的贴现率之间的相关性。

Drug use may be conceptualized as an impulsive choice because the user prefers the small immediate reinforcing consequences of taking drugs (e.g., getting high) over the large-delayed reinforcing consequences of drug abstinence (e.g., occupational success, improved interpersonal relations, etc.). Several studies have illustrated that drug-dependent individuals discount the value of delayed reinforcers more than non-drug- users. In these studies, psychometric techniques are used to determine the subjective value of a series of large-delayed rewards (e.g. $1,000 delivered in 1 year.) A shortcoming of this conceptual model is that the large-delayed benefits of abstinence are rarely given in a lump sum after a single delay. Instead, these benefits are typically distributed in smaller amounts over several delays (e.g., slightly improved relations with a spouse seen daily over many years). Thus, the first aim of the proposed study is to compare discounting rates across situations in which the large- delayed reinforcer is delivered in a lump sum following a single delay or delivered in smaller amounts following a series of delays. A 2 x 2 mixed factorial design will be used in which diagnosis (drug dependent vs. non- drug user) is a between-subjects factor and choice situation )delayed rewards delivered in a lump sum vs. distributed over time) is a whin- subjects factor. The second aim of the proposed study is to explore the relation between the discounting of delayed and high-priced rewards. Several studies have recently suggested that animals and humans discount high-priced rewards in a manner similar to the way they discount the value of delayed rewards available at a range of prices (price operationalized as effort required to obtain each reward). The correlation between price elasticity of demand (a measure of sensitivity to price increases) and discounting rates of individual participants will be assessed.