Inter-Temporal Trade-offs in the Risky Decisions of Cocaine Addicts

描述(由申请人提供)：可卡因的使用及其相关的危险性行为(例如，与多个伴侣发生性关系、不一致地使用避孕套、以性行为换取毒品或金钱)是艾滋病毒持续传播的重要因素。然而，人们对性、毒品和金钱在这一人群中的价值知之甚少，也不知道调节这些权衡的神经过程受到干扰。在本申请中，我们直接解决了PAS-07-324的目标，以增加对影响高危性行为决策的可卡因成瘾过程的理解。我们建议通过融合慢性可卡因使用者(CCU)做出的病理决定的行为和神经基础来探索这一点，这些决定不是使用基于模型的方法、行为决策任务和功能磁共振成像(FMRI)做出的。我们的总体假设是，成瘾过程导致决策系统功能失调，而决策系统是CCU从事危险性行为的基础；换句话说，CCU从事危险的性行为是因为它们忽视了执行系统(前额叶皮质)和过度活跃的脉冲系统(边缘大脑回路)导致的未来结果。为了加深我们对影响危险性行为决策的可卡因上瘾过程的理解，我们将获得CCU对相关商品(性、毒品、金钱)估值的迫切需要的信息，认识到这些商品具有多种功能，并可能以新的方式相互作用。我们将研究不同商品的估值和跨期选择，以获得对CCU做出的决定的新见解，包括与以性交易毒品或金钱的高风险行为密切相关的决定，以及它们与娱乐性可卡因使用者(RCU)和社区控制参与者(CCP)有何不同。我们假设，不同的商品将表现出不同的影响概况，这取决于其他商品的可获得性(相同或不同的商品)、它们的时间位置(直接或稍后)以及主体群体(CCU、RCU、CCP)。此外，考虑到现有的数据，我们预计系统地复制货币折扣(现在的钱与以后的钱)将预测新人群(CCU)中的艾滋病毒风险行为。神经相关因素的纳入将使我们能够首次确定不同神经行为决策系统在预测艾滋病毒风险行为的决策中的作用。通过将货币折扣与商品内部和跨商品的毒品和性行为折扣进行比较，我们将确定新的折扣程序和相关的神经过程是否比货币折扣更能预测风险行为。该项目的完成将提供有关神经评估系统的大量新信息，这些系统会因成瘾而改变，并导致危险的性行为。了解感兴趣的商品如何相互作用，以及参与估值的神经系统，可能会提出新的方法来改变病理估值，并影响与艾滋病毒传播相关的风险行为。

DESCRIPTION (provided by applicant): Cocaine use and its associated risky sexual behaviors (e.g., sex with multiple partners, inconsistent condom use, trading sex for drugs or money) represent a significant contributor to the ongoing spread of HIV. However, little is known about how sex, drugs, and money are valued in this population, nor about the perturbed neural processes mediating these tradeoffs. In this application, we directly address the objective of PAS-07-324 to increase understanding of processes of cocaine addiction that influence decisions about high-risk sexual behavior. We propose to explore this via the convergence of behavioral and neural underpinnings of the pathological decisions made by Chronic Cocaine Users (CCUs) not in treatment using a model-based approach, behavioral decision tasks, and functional magnetic resonance imaging (fMRI). Our overall hypothesis is that the processes of addiction result in a dysfunctional decision system that underlies the risky sexual behavior engaged in by CCUs; in other words, CCUs engage in risky sexual behavior because they discount future outcomes as a result of a hypoactive executive system (in prefrontal cortex) and a hyperactive impulsive system (in limbic brain circuits). To improve our understanding of cocaine addiction processes that influence decisions about risky sexual behavior, we will obtain critically needed information about the CCU's valuation of relevant commodities (sex, drugs, money), recognizing that these commodities serve multiple functions and may interact with one another in novel ways. We will study valuation and inter-temporal choice within and across different commodities to gain new insights into the decisions made by CCUs, including decisions closely tied to the high-risk behavior of trading sex for drugs or money, and how they differ from Recreational Cocaine Users (RCUs) and Community Control Participants (CCPs). We hypothesize that different commodities will show different profiles of effect depending on availability of other commodities (same or different commodities), their temporal location (immediate or later), and the subject group (CCUs, RCUs, CCPs). Additionally, given the existing data, we anticipate systematically replicating that the discounting of money (money now vs. later) will be predictive of HIV risk behavior in a new population (CCUs). The inclusion of neural correlates will permit us to identify for the first time the role of different neurobehavioral decision systems in decision making predictive of HIV risk behavior. By comparing money discounting to discounting of drug and sexual activity within and across commodities, we will determine whether novel discounting procedures and associated neural processes are more predictive of risky behavior than money discounting. Completion of this project will provide substantial new information about neural valuation systems that are altered by addiction and lead to risky sexual behavior. Understanding how the commodities of interest interact with one another and the neural systems that participate in that valuation may suggest new approaches to alter the pathologic valuation and impact risky behavior associated with the spread of HIV.