Department of Psychology, University of Wisconsin-Madison, Madison, WI, USA.
Psychopharmacology (Berl). 2011 Nov;218(1):217-27. doi: 10.1007/s00213-011-2304-6. Epub 2011 Apr 19.
Clarification of alcohol's effect on stress response during threat is critical to understand motivation for alcohol use and related alcohol-use disorders. Evaluation of stress response dampening (SRD) effects of alcohol has been limited by nonsystematic use of varied experimental methods and measures.
This experiment parametrically varied alcohol dose and shock threat intensity among social drinkers to examine their effects on startle potentiation, a physiological measure of the affective component of the stress response.
Ninety-six participants were assigned to one of four beverage groups: placebo and target blood alcohol concentration (BAC) groups of 0.04%, 0.075%, and 0.11%. Participants viewed colored cues presented in shock and no-shock blocks. Distinct colored cues predicted imminent low, moderate, or high intensity electric shock administration. Startle potentiation during shock threat relative to no-shock cues indexed affective response.
High threat increased startle potentiation relative to moderate/low intensity threat. Startle potentiation decreased as BAC increased. Threat intensity moderated this BAC effect with the strongest BAC effect observed during high threat. Analysis of individual difference moderators revealed reduced effect of BAC among heavier, more problematic drinkers.
Clear alcohol SRD effects were observed. These SRD effects were greatest at higher BACs and during more potent threat. Failure to account for these factors may partially explain inconsistent findings in past laboratory SRD research. Furthermore, they suggest greater reinforcement from alcohol at higher doses and among individuals with greater stress. Moderation of SRD effects by alcohol consumption and problems point to possible important risk factors.
阐明酒精对威胁下应激反应的影响对于理解酒精使用的动机和相关的酒精使用障碍至关重要。由于未能系统地使用各种实验方法和措施，酒精对应激反应抑制（SRD）作用的评估受到了限制。
本实验在社交饮酒者中参数化地改变酒精剂量和冲击威胁强度，以研究它们对惊吓增强（startle potentiation）的影响，这是应激反应情感成分的一种生理测量。
96 名参与者被分配到四个饮料组之一：安慰剂和目标血液酒精浓度（BAC）组为 0.04%、0.075%和 0.11%。参与者观看了在冲击和非冲击块中呈现的彩色提示。不同的彩色提示预测即将到来的低、中或高强度电击。与非冲击提示相比，冲击威胁期间的惊吓增强指数情感反应。
高威胁相对于中/低强度威胁增加了惊吓增强。随着 BAC 的增加，惊吓增强减少。威胁强度调节了这种 BAC 效应，在高威胁下观察到最强的 BAC 效应。个体差异调节因素的分析表明，在较重和更有问题的饮酒者中，BAC 的影响降低。
观察到明显的酒精 SRD 作用。这些 SRD 作用在较高的 BAC 和更强的威胁下最大。过去实验室 SRD 研究中发现的不一致结果可能部分是由于未能考虑到这些因素。此外，它们表明在更高的剂量和在压力更大的个体中，酒精的强化作用更大。酒精消耗和问题对 SRD 作用的调节表明可能存在重要的风险因素。
