Psychology Department, Stanford University, Stanford, CA 94305, USA.
Neuroimage. 2011 Mar 1;55(1):401-10. doi: 10.1016/j.neuroimage.2010.11.040. Epub 2010 Nov 18.
Anticipatory emotional responses play a crucial role in preparing individuals for impending challenges. They do this by triggering a coordinated set of changes in behavioral, autonomic, and neural response systems. In the present study, we examined the biobehavioral impact of varying levels of anticipatory anxiety, using a shock anticipation task in which unpredictable electric shocks were threatened and delivered to the wrist at variable intervals and intensities (safe, medium, strong). This permitted investigation of a dynamic range of anticipatory anxiety responses. In two studies, 95 and 51 healthy female participants, respectively, underwent this shock anticipation task while providing continuous ratings of anxiety experience and electrodermal responding (Study 1) and during fMRI BOLD neuroimaging (Study 2). Results indicated a step-wise pattern of responding in anxiety experience and electrodermal responses. Several brain regions showed robust responses to shock anticipation relative to safe trials, including the hypothalamus, periaqueductal gray, caudate, precentral gyrus, thalamus, insula, ventrolateral PFC, dorsomedial PFC, and ACC. A subset of these regions demonstrated a linear pattern of increased responding from safe to medium to strong trials, including the bilateral insula, ACC, and inferior frontal gyrus. These responses were modulated by individual differences in neuroticism, such that those high in neuroticism showed exaggerated anxiety experience across the entire task, and reduced brain activation from medium to strong trials in a subset of brain regions. These findings suggest that individual differences in neuroticism may influence sensitivity to anticipatory threat and provide new insights into the mechanism through which neuroticism may confer risk for developing anxiety disorders via dysregulated anticipatory responses.
预期情绪反应在为即将到来的挑战做准备方面起着至关重要的作用。它们通过触发行为、自主和神经反应系统的协调变化来实现这一点。在本研究中，我们使用了一种预期性电击任务来检查不同程度的预期性焦虑的生物行为影响，在该任务中，不可预测的电击会以不同的间隔和强度（安全、中等、强）威胁并施加到手腕上。这使得可以研究预期性焦虑反应的动态范围。在两项研究中，分别有 95 名和 51 名健康女性参与者接受了这种电击预期任务，同时提供了焦虑体验和皮肤电反应的连续评分（研究 1）和 fMRI BOLD 神经影像学（研究 2）。结果表明，焦虑体验和皮肤电反应呈现出逐步的反应模式。与安全试验相比，几个大脑区域对电击预期表现出强烈的反应，包括下丘脑、导水管周围灰质、尾状核、中央前回、丘脑、岛叶、腹外侧前额叶、背内侧前额叶和 ACC。这些区域中的一部分表现出从安全到中等到强试验的线性反应模式，包括双侧岛叶、ACC 和额下回。这些反应受到神经质的个体差异的调节，即那些神经质水平较高的人在整个任务中表现出更强烈的焦虑体验，并且在一部分大脑区域中，从中等到强试验的大脑激活减少。这些发现表明，神经质的个体差异可能会影响对预期性威胁的敏感性，并为神经质可能通过失调的预期反应导致焦虑障碍风险的机制提供新的见解。
