Impulsivity and Stimulant Drug Reward

描述（由申请人提供）：本项目旨在研究冲动与药物奖励敏感性之间的关系。冲动和对药物奖励效应的敏感是滥用药物的两个已知危险因素。冲动被认为是造成虐待的一个原因。它是一个多方面的结构，包括冲动行为（难度控制行为）；冲动选择（难以延迟满足）；冲动注意力（难以专注于手头的任务）；以及冲动性格（易冲动）。对奖励的敏感性也被认为会影响对药物使用的敏感性，尽管有人认为风险与对奖励的敏感性高于平均水平或低于平均水平有关。冲动和奖励敏感性之间的关系还不太清楚。这两种结构可能独立地增加药物滥用的风险，或者它们可能相互关联。有证据表明，高冲动性与低奖励敏感性，特别是对药物奖励效应的敏感性有关。此外，有神经生物学证据表明，冲动和药物奖励都与多巴胺活动有关，进一步表明两者可能存在关联。当前提案的目的是检查对冲动的每个子成分高和低的个体对兴奋剂药物安非他明（0-20毫克），MDMA（0-1.5毫克/公斤）和咖啡因（0-200毫克）的主观奖励效应的敏感性。据推测，与非冲动个体相比，高度冲动的个体会表现出压抑的主观反应。此外，该提案将测试这种对奖励的抑制反应是否也可以在对甜味的反应中观察到，这是一种非药物奖励的衡量标准，还是只针对滥用药物。

DESCRIPTION (provided by applicant): This project is designed to investigate associations between impulsivity and sensitivity to drug reward. Impulsivity and sensitivity to the rewarding effects of drugs are two known risk factors for drug abuse. Impulsivity is thought to have a causal role in the onset of abuse. It is a multi-faceted construct comprised of impulsive action (difficulty controlling behavior); impulsive choice (difficulty delaying gratification); impulsive attention (difficulty focusing on the task at hand); and impulsive personality (predisposition to rash action). Sensitivity to reward is also thought to influence susceptibility to use drugs, although arguments have been made that risk is related to both higher than average or lower than average sensitivity to reward. The relationship between impulsivity and reward sensitivity is poorly understood. The two constructs may independently contribute to risk for drug abuse, or they could be related to each other. There is some evidence that high impulsivity is related to low reward sensitivity, especially sensitivity to the rewarding effects of drugs. Additionally, thee is neurobiological evidence linking both impulsivity and drug reward to dopamine activity, further suggesting that the two might be related. The aim of the current proposal is to examine sensitivity to the subjective rewarding effects of the stimulant drugs amphetamine (0-20 mg), MDMA (0-1.5 mg/kg), and caffeine (0-200 mg) in individuals high and low on each of the sub-components of impulsivity. It is hypothesized that highly impulsive individuals will exhibit a dampened subjective response compared to non-impulsive individuals. Additionally, the proposal will test if this dampened response to reward is also observable in response to sweet taste liking, a measure of non-drug reward, or if it is specific to drugs of abuse.