This research was supported by Grants R01AA15384 from the National Institute on Alcohol Abuse and Alcoholism and 5R01DA033809-02 from the National Institute of Drug Abuse to John J. Curtin.

当地伦理委员会已批准下列程序，谁曾在此过程中参与的所有参与者都给予知情同意书。对于心理生理测量和刺激呈现的更多细节，请参见30,27。 1，肌电图（EMG）记录准备<ol><li>请参与者用肥皂彻底清洗面部，特别要注意目标传感器的位置，这是位于下方的一只眼睛，并在参与者的额头中间（ 见图2）。 </li><li>座位在实验室舒适的座椅直立的参与者。 </li><li>准备参加者的皮肤肌电图测量。 <ol><li>清洁用酒精垫的目标传感器的位置。 </li><li>用小纱布垫，以进一步去除污垢和死皮细胞，它可以阻碍测量Ø请用坚韧不拔的去角质凝胶的相同位置F表示肌电活动。 </li></ol></li><li>准备和附加肌电电极。 <ol><li>填用注射器和钝针所有银 - 氯化银（银 - 氯化银）传感器杯子的导电凝胶。 </li><li>连接大（ 例如，8毫米）银-氯化银传感器参与者的额头使用粘合剂领中心。 </li><li>连接两个额外的小（ 如 4毫米），银-氯化银下方的参与者的眼睛用胶粘剂衣领传感器。将第一，这些小的传感器在与光瞳在向前视线和第二传感器1-2厘米横向于所述第一线（ 图2，参见27）。不要让粘合衣领重叠，因为这可能会增加运动伪影。防止凝胶溢出，以避免形成两个传感器眼睛下方之间的凝胶桥，因为这将导致电流通过桥流动并削弱EMG活动的测量。 </li></ol></li><li>开始对T肌电采集软件他生理电脑，并要求参与者闪烁了几下，以验证该肌电反应被记录正常，且眨眼可以将数据采集软件的显示屏上观察（ 见图3A的肌电活动有关联的一个例子闪烁）。 </li><li>检查每个传感器的阻抗。 注:许多实验室需要低于10kΩ的阻抗（或更保守，5kΩ的），但实际可容许的阈值测量的阻抗水平取决于许多变量，如实验设计，放大器的设计和实际限制相对于时间的需要，以降低阻抗及参与人群。无论如何，高阻抗会增加肌电信号的易感性电气神器，这可能是有问题的（60 Hz的噪声， 见图3B）。 </li><li>广场上的参与者的头耳机。 </li></ol>创2基线测量ERAL惊恐反应 注:该评估还有助于进一步的，观察者惊吓反应之前刚刚任务之前交付的3习惯探头启动31。包括一般的惊恐反应在惊吓增效的统计分析协变量增加统计力量在和参与者之间的效果检测。一般惊跳反应可能也反映了一个有趣的个体差异衡量12,32。 <ol><li>请参与者获取基线任务开始前舒适，并尽可能保持始终保持与他们的双脚平放在地板上的任务。参加运动可以引入神器成肌电信号（ 见图3C）。 </li><li>提醒他们可以在实验过程中的任何一点终止其参与的参与者。在这两种使用视频和音频饲料试验室监控参与者基线评估和主要任务。 </li><li>保存肌电图信号采集软件的生理计算机并启动了刺激控制电脑上的刺激呈现软件。 </li><li>呈现的参加者用一系列有色的正方形，将在主任务中使用，但还没有被配对的电击。这些线索的一个子集与线索之间的间隔期间存在不惊人死不休的探针。时序参数为时间线索，线索之间的时间间隔，以及惊人死不休的探针必须匹配的主要任务参数。一般的惊恐反应可靠的测量需要至少4个探头的呈现。这个基线任务大约需要5分钟才能完成。 </li><li>平均起来参加的高峰肌电惊吓反应到每个探头吓一跳基线过程中，产生将作为该与会者的普遍惊恐反应一个值（参见步骤6.1-6.6如何处理肌电图的数据）。包括:一般的惊恐反应作为一种添加剂或涉及惊吓增效统计模型的交互式协（见步骤6.8）。 </li></ol> 3，抗冲击性阈值评估<ol><li>加盖标准的医用胶布2冲击电极参与者的手（ 如手食指和无名指末节指骨），33 - 35。 </li><li>目前，参加了一系列的日益激烈电击。在每次冲击给药，要求参与者评价他们如何厌恶的发现震惊于100分。要求他们用0评级，如果他们不能感到震惊全中，50震撼，他们认为是不舒服的第一级评级，以及100的冲击，他们可以容忍的最高水平的评级。 </li><li>指示，这是重要的，以精确地报告他们能容忍最高休克的参与者。参与者不应bê告知，他们的报告将影响他们获得的实际冲击，因为这可能会导致偏差在他们的报告。 </li><li>停止防震能力评估，一旦参与者速率的冲击为100记录的震撼级和管理的冲击在这个级别的威胁概率任务，以控制震动敏感性的个体差异。 注:电击是给予每个参与者的主观最大冲击耐受阈值。但是，较低强度的冲击也用21。无论如何，重要的是选择的震动强度是足以引起所有参与者健壮负情感反应和相关的惊跳增强作用。 </li></ol> 4，威胁概率任务<ol><li>提供一个封面故事，鼓励关注整个任务的参与者。 注:某些参与者可能难以保持关注throughoUT斯达康的威胁概率任务。的封面文章，研究人员可以告诉与会者，以鼓励重视这项工作的一个例子是告诉参与者，研究人员有兴趣在一个简单的，重复性的视觉相似任务任务测量了参与者的关注随着时间的能力空中交通管制要求。 </li><li>提供每个条件一般的任务信息和具体的线索冲击突发参与者。 <ol><li>指示该任务持续约20分钟的参与者。 </li><li>指导这项任务包括持续5秒，平均每次相隔15-20秒线索参与者。 </li><li>告知该线索组织成组，每个组各持续2-3分钟的参与者。 </li><li>指示参与者，有三种类型的套，20％休克套，100％休克组和无休克集。 </li><li>指导参与者，他们将收到冲击的端的约1每5线索在20％休克套和5每5线索在100％休克套。 </li><li>确保他们不会收到任何冲击在任何时候在没有震动台或在任一台的线索（ITI）的发言之间的时间参加。 </li><li>让参加者询问有关任务的问题在说明书的末尾。在此之后，问答，参与者，以确保他们完全理解了冲击不时之需。提醒他们可以在实验过程中的任何一点终止其参与的参与者。 </li></ol></li><li>保存肌电图信号采集软件的生理计算机和刺激控制计算机将控制任务的刺激上启动刺激呈现软件。 </li><li>仔细监视参与者的自愿运动，闭眼，或过度不适。 </li></ol> 5，后期实验<ol><li>该提示的威胁任务后，管理一个调查问卷，参与者以确认威胁突发事件进行任务期间得到很好的理解。要求参与者评估他们如何焦虑或恐惧是当他们看到每个威胁提示以5点量表，从1（一点也不焦虑/恐惧）到5（非常焦虑/恐惧）。 注意:使用两个单独的威胁任务的不确定性来自布拉德福德等 7,25结果表明，导致自我报告的焦虑的密切配合是惊吓增效的格局。 </li><li>汇报的参与者，补偿他们的时间，他们辞退。 </li><li>清洗和消毒所有的传感器。 </li></ol> 6，数据处理，还原与分析 注:研究人员可以完成数据处理和减少各种软件包。 EEGLAB 36是一个免费的，开源的工具箱内Matlab的&lt;分析心理生理数据SUP&gt; 37。对于数据处理和削减步骤的模板EEGLAB脚本请参阅补充材料。数据处理和减少遵循公布的指导方针27。对于未处理（生）连续肌电周边1惊吓探测信号的几秒钟的显示， 见图4A。 <ol><li>套用前后的高通滤波器（4 阶 28 Hz的巴特沃斯滤波器），以原连续肌电图（ 见图4A，B）。 </li><li>整流滤波后连续肌电图（参见图4C）。 </li><li>使用前后4 阶 30 Hz的巴特沃斯低通滤波器平滑整流肌电图信号（ 见图4D）。 </li><li>划时代的平滑连续的信号，（-50到0毫​​秒）从整个epochedš保持周围的声惊吓探针发病和"基线正确"的epoched信号中减去预先探测基线的平均-50℃至250毫秒ignal（ 见图4E）。 </li><li>分数从每个时代为20和100毫秒后探头发病的最大响应惊吓反应（ 见图4F）。 </li><li>拒绝与过度的伪影的试验（ 例如，过度的变形，在预探测基线，参见图5）。 注意:信号包含在预先探测基线大于40μV的挠度可以被识别为伪像。 </li><li>为每个任务状态中历元平均惊恐反应（无冲击，20％的冲击，100％休克）（参见图6A）。 <ol><li>计算惊跳增强作用不确定休克为平均惊恐反应之间的差异在20％的冲击线索惊跳探针与无休克线索（参见图6B）。注:20％条件期间ITI探针惊跳反应也可以测量以研究预期的相关一些概念问题的效果和持续惊跳增效焦虑6,21 tualizations。 </li><li>计算惊跳增强作用对某些休克为平均惊恐反应之间的差异，以在100％休克线索惊跳探针与无休克线索（参见图6B）。 </li></ol></li><li>分析使用的是一般线性模型与工作条件和一般的惊吓反应（步骤2.5计算）作为添加剂或交互协32重复测量惊吓增效。 </li></ol>

The authors declare that they have no competing financial interests.

威胁概率任务可用于通过评估惊跳增强作用，以低概率（不确定）和电击的概率很高（一定）的威胁来研究焦虑和恐惧的表达。在该任务中所使用的主要取决于测量和威胁意外事件可以与啮齿类，非人灵长类和人类中使用，因此，对于研究表达的负面影响13,18,40提供一种优异的平移工具。惊吓增效电击的威胁有明确的连接，防御系统激活，可耐意志控制，并有明确的神经生物学基板。这是...

威胁概率任务的总体目标是通过实验解开应对低概率（ 即不确定性）威胁的恐惧反应概率高（ 即一定的）威胁的焦虑的表情。当威胁某些方面是定义不清发生​​的不确定性。而焦虑能够以多种方式进行说明，而加剧响应低概率或其他不确定负面事件是一个显着的临床症状在焦虑症1,2。此外，增加焦虑相关的生理过程中的冲击不明朗的威胁与恐惧有关的生理过程中的冲击一定的威胁实验室的任务可能会提供一个生理标志为焦虑症3响应响应。抑制焦虑不确定的威胁，特别是可能是应激反应抑制药物如酒精4-7性能的一个重要组成部分。在UNC增加焦虑ERTAIN威胁可能标志着大脑的压力下电路长期用药4,8àneuroadaptation。因此，威胁概率任务提供了消极的情感和独特的情感状态（焦虑，恐惧）在研究精神病理学使用，药物使用/滥用和情感的科学客观的衡量。因此，它可以是一个强大的工具，供有兴趣的精神病理病因和情感个体差异临床上和情感上的科学家。 用于研究的人类情感传统方法情感科学家们使用了许多措施和范式来研究人类的情感9，但其中大部分都不能提供的威胁概率任务中来解析其他负面情绪焦虑必要的精度，如恐惧。例如，自报是常用的，但它可能会受到需求的特点和其他形式的反应偏差的。参加者可能不ABLE要焦虑和恐惧，他们的报告，底层神经生物学机制的连接准确区分是远端的最好的。此外，自我报告必须经常进行追溯自反省和报告的过程中可能会以其他方式改变的情感刺激参与者的经验。当然，回顾性报告患有记忆干扰和退化。 Psychophysiologists通常衡量一个影响操作，涉及到演示文稿的情感动人画面10时的情绪。这张照片查看任务很好的验证，较少受自我报告的不足之处，并导致有关的情感反应的个体差异及其对精神病理学11,12贡献了许多重要见解。然而，只有广泛的负面影响是这幅画查看任务不允许对不同的负面情绪，如焦虑和恐惧在研究过程中测量whicH可与威胁概率任务来测量。期间引起的负面影响，但这些方法可能是太昂贵了许多研究工作中的情感神经科学家经常测量功能性磁共振成像（fMRI）技术。此外，功能磁共振成像方法的空间分辨率和时间分辨率，目前有限的，难以让fMRI来解开认为与焦虑相对于其他情绪相关的神经结构。更重要的是，任何类型的负的良好定义的fMRI指数影响也尚未确立。 翻译研究与利用的惊吓反应的动物与动物提供了从恐惧焦虑理清所需要的精度的第一个例子的基础研究之后，威胁概率任务为蓝本。神经科学家已经使用小心控制病变的研究与啮齿动物模型的焦虑和恐惧使用差分应对不确定性和certa触电的线索威胁。这项工作阐明，以低概率，含糊不清的，远端或其他不确定休克焦虑相关的反应的重要差异与恐惧有关的反应极有可能，明确的规定，即将一定的冲击13。不确定的威胁，引起冻结和动物过度警觉，而某些威胁引发主动回避，防御攻击，或两者14。迫在眉睫，一定威胁注意力集中在威胁自己，而远，时间上不确定的威胁，鼓励分散关注整体环境15 - 17。响应时间不确定的威胁似乎被持续的，而响应于某些威胁是相位和时间锁定到的威胁13。在相关的工作中，病变的研究表明，响应于不确定的威胁是由促肾上腺皮质激素释放因子和去甲肾上腺素途径通过横向选择性地介杏仁核的中央核和终纹18的床细胞核分裂。大部分工作使用的听觉惊恐反应作为主要取决于测量13，这是在威胁概率任务中使用的相同依赖性度量的增强作用。惊跳响应电路的神经生物学衬底已被广泛研究以明确连接的发现，以积极应对不确定和某些威胁19,20的脑部结构。惊吓反应可以在许多物种提供了强大的翻译工具，研究情绪进行评估。在人类的惊吓反应条件反射发生反应突然激烈的听觉刺激。惊跳是最经常被放置在眼睛的眼轮匝肌（盖关闭）肌肉肌电图（EMG）电极来测量在人。当一个生物体呈现恐吓stimul惊人死不休的相关肌电活​​动得到增强我们如即将发生的电击相对于无威胁的刺激19。 无冲击，可预见的冲击，不可预知的冲击（NPU）的任务和威胁的不确定性威胁概率任务是由Grillon和同事的启发，当这些研究人员推出了采用惊吓增效的学习焦虑和恐惧的人与无冲击，可预见的冲击，不可预知的冲击（NPU）任务21。在西工大任务的可预测的情况下，冲击是100％的线索队伍，发生在一个一致的，已知的时间（简要提示呈现结束）。在西工大任务的不可预知的情况下，震荡是完全不可预测的。患者创伤后应激和恐慌症期间不可预测的，但不可预测的冲击，在西工大任务22,23表现出选择性增加惊跳增强作用。在其他工作中，药物处方来治疗焦虑症有惊吓potentiati的影响更大在不可预知的冲击比预测的冲击，在西工大任务24时期间。在酒精的抗焦虑作用的研究，莫葛博士和科廷科技大学4所使用的西工大任务来表明中等剂量的酒精选择性降低时不可预知的，但不可预测的冲击的威胁惊吓增效。不确定因素是多方面的，在西工大任务的不可预知条件下的冲击是不确定的问候双方如果他们出现（概率的不确定性）， 当它们发生（时间不确定）。许多理论认为，不确定性的WHEN尺寸生产的焦虑19的关键。然而，从科廷科技大学等 5数据表明一个共同的机制，在不同类型的不确定性的焦虑启发。这里所描述的威胁概率任务操纵有关如果在持有的不确定性的所有其他方面不变从而清楚会发生震动的不确定性什么方面的不确定性是负责该任务呈现效果。使用不惊人死不休增效来威胁线索的任务是灵活的，还可以通过情感的科学家修改操作有关，其中冲击将要发生的25和多么糟糕，他们将7,26的不确定性。所有这些任务的，威胁概率的任务是最简单的，由于不确定性的一个方面，最简单的实现来解释它的工作重心之一，由于其包含的只有两个威胁的不确定性变量（低概率，高冲击的概率）。 威胁概率任务在威胁概率任务，参与者从阴极射线管（CRT）显示器坐在约1.5m。威胁线索都显示在监视器上，每次5秒，可变的持续时间ITI（范围= 15-20秒）。威胁线索被分成几组两个冲击威胁的条件和一个无威胁的情况（见<stroNG&gt;图1）。在这两种威胁的条件下200毫秒时间震荡在4.5秒被送入提示呈现时代到参加者的手指。在100％的威胁概率条件下，冲击正在呈现每个线索的过程中传递。在20％的威胁概率条件下，冲击被介绍1，每5线索的过程中传递。与会者认为每个威胁概率条件下两套（15线索总量）。与会者还认为，两个中性集，信号没有威胁线索（无威胁的线索，线索15条记录）。在监视器上显示文本通知下一组类型的参与者。在显示屏的左上角的整组期间显示的标签的集合类型。不同颜色的线索被用来为每​​个条件，以便各组的参加者的意识。在整个任务中，刺激呈现程序提供了声惊吓探针的102分贝白噪声50毫秒脉冲的形式参加通过耳机提供近瞬时的上升时间。听觉惊恐探针在4秒内递送到线索的子集的呈现。额外探针递送在13秒和15秒后提示的工业培训期间偏移减小探针的可预测性。任何呈现视觉刺激之前，任务开始交付3听觉惊恐的探针主要任务测量之前立即，观察者的惊恐反应。研究者平衡以控制为习惯和致敏作用27,28跨学科内条件的听觉惊恐探针的序列位置。对于一个完全抵消一系列试验的威胁概率任务的一个例子见补充材料。 威胁概率任务已经用于证明低概率（不确定）单独休克是足以引起焦虑和允许的醇的抗焦虑作用的评估<sup&gt; 6。与相关的大麻使用者的初步研究表明威胁概率任务，也可用于评估停药29的效果。因此，威胁概率任务提供了一个容易实现的，可以替代昂贵和不够精确的方法不同的负面情绪状态（ 例如，焦虑和恐惧）的研究精神病理学，药物使用/滥用，和广泛的情感科学的客观的衡量标准。

<table><tbody><tr><td>Amplifier</td><td>Numerous options</td><td></td><td>See Curtin, Lorenzo, and Allen (2007) for a list of vendors.</td></tr><tr><td>Small Ag/AgCl EMG Sensors</td><td><a href="http://www.discountdisposables.com/" target="_blank"><img src="/img/new_window.png" /> Discount Disposables</a></td><td>TDE-023-Y-ZZ-S</td><td>4 mm, and 48 in lead length</td></tr><tr><td>Large Ag/AgCl EMG sensor</td><td><a href="http://www.discountdisposables.com/" target="_blank"><img src="/img/new_window.png" /> Discount Disposables</a></td><td>TDE-022-Y-ZZ-S</td><td>8 mm, and 48 in lead length</td></tr><tr><td>Small electrode collars</td><td><a href="http://www.discountdisposables.com/" target="_blank"><img src="/img/new_window.png" /> Discount Disposables</a></td><td>TD-23</td><td>5 mm</td></tr><tr><td>Large electrode collars</td><td><a href="http://www.discountdisposables.com/" target="_blank"><img src="/img/new_window.png" /> Discount Disposables</a></td><td>TD-22</td><td>8 mm</td></tr><tr><td>Shock box</td><td>Custom</td><td>Custom</td><td>See supplemental material for a circuit diagram for the custom shock box used by the Curtin laboratory. An example of a commerical shock box can be found at: &lt;a href=&quot;http://www.psychlab.com/stim_SHK_shockers.html&quot;&gt;http://www.psychlab.com/stim_SHK_shockers.html&lt;/a&gt;.</td></tr><tr><td>Alcohol pads</td><td><a href="http://www.fishersci.com/ecomm/servlet/home?storeId=10652" target="_blank"><img src="/img/new_window.png" /> Fisher Scientific</a></td><td>06-669-72</td><td></td></tr><tr><td>Exfoliant gel</td><td><a href="http://www.weaverandcompany.com/index.html" target="_blank"><img src="/img/new_window.png" /> Weaver and Company</a></td><td>NuPrep</td><td></td></tr><tr><td>Conductive Gel</td><td><a href="http://www.electro-cap.com/" target="_blank"><img src="/img/new_window.png" /> Electro-Cap International</a></td><td>ECA E9</td><td></td></tr><tr><td>Gauze pads</td><td><a href="http://www.neuroscan.com/supplies.cfm" target="_blank"><img src="/img/new_window.png" /> Neuromedical Supplies</a></td><td>95000025</td><td></td></tr><tr><td>Blunt Needle</td><td><a href="http://www.electro-cap.com/" target="_blank"><img src="/img/new_window.png" /> Electro-Cap International</a></td><td>E8B</td><td></td></tr><tr><td>Medical tape</td><td><a href="http://www.neuroscan.com/supplies.cfm" target="_blank"><img src="/img/new_window.png" /> Neuromedical Supplies</a></td><td>95000032</td><td></td></tr><tr><td>Electrode Sterilizing Solution</td><td><a href="http://www.buyemp.com" target="_blank"><img src="/img/new_window.png" /> Emergency Medical Products:</a></td><td>MX-2800</td><td>Gloves should be warn when handling metricide.</td></tr><tr><td>Headphones</td><td><a href="http://en-us.sennheiser.com/" target="_blank"><img src="/img/new_window.png" /> Sennheiser</a></td><td>4974</td><td>Head phones should be capable of repeatedly delivering startle probe&amp;rsquo;s at the level chosen by experimenters (&lt;em&gt;e.g.&lt;/em&gt;102 dB).</td></tr><tr><td>Participant monitoring camera</td><td><a href="http://www.polaris.com/en-us/home.aspx" target="_blank"><img src="/img/new_window.png" /> PolarisUSA</a></td><td>BC-660B</td><td>Infrared capable camera so participant can be monitored while lights are off in experiment room.</td></tr><tr><td>Infrared panel</td><td>PolarisUSA</td><td>IR-TILE</td><td>http://www.polaris.com/en-us/home.aspx</td></tr><tr><td>Video monitor for participant monitoring</td><td><a href="http://www.marshall-usa.com/IVS/monitors/M-Pro_CCTV_19.html" target="_blank"><img src="/img/new_window.png" /> Marshall Electronics</a></td><td>M-Pro CCTV 19</td><td></td></tr><tr><td>Stimulus Computer</td><td><a href="http://www.dell.com/" target="_blank"><img src="/img/new_window.png" /> Dell</a></td><td>Dell Optiplex3010</td><td>Most modern computers appropriate</td></tr><tr><td>Sound card (Stimulus computer)</td><td><a href="http://us.store.creative.com/Creative-Sound-Blaster-XFi-Titanium-HD/M/B0041OUA38.htm" target="_blank"><img src="/img/new_window.png" /> Creative</a></td><td>70SB127000002</td><td>The sound card delivers the startle probes. An example of a stand alone noise generator can be found at: &lt;a href=&quot;http://www.psychlab.com/stim_TG_WN_sound.html#&quot;&gt;http://www.psychlab.com/stim_TG_WN_sound.html#&lt;/a&gt;.</td></tr><tr><td>I/O card (Stimulus computer)</td><td><a href="http://www.mccdaq.com/pci-data-acquisition/PCI-DIO24.aspx" target="_blank"><img src="/img/new_window.png" /> Measurement Computing</a></td><td>PCI-DIO24</td><td>I/O card allows control of shock box and communication of event markers (&lt;em&gt;e.g.&lt;/em&gt; for startle probe occurrence) to data collection computer.</td></tr><tr><td>Stimulus control software</td><td><a href="http://www.psychtoolbox.org/" target="_blank"><img src="/img/new_window.png" /> Psychtoolbox</a></td><td></td><td>Open source (free) toolbox based in Matlab.</td></tr><tr><td>Computational platform for stimulus control and data reduction</td><td><a href="http://www.mathworks.com/products/matlab/" target="_blank"><img src="/img/new_window.png" /> MathWorks</a></td><td></td><td>Required to use Psychtoolbox and EEGLAB (below).</td></tr><tr><td>Data collection computer</td><td><a href="http://www.dell.com/" target="_blank"><img src="/img/new_window.png" /> Dell</a></td><td>Dell Optiplex3010</td><td>Most modern computers are appropriate</td></tr><tr><td>Psychophysiology acquisition software</td><td>Numerous options</td><td></td><td>See Curtin, Lorenzo, and Allen (2007) for a list of vendors.</td></tr><tr><td>Stimulus Monitor</td><td><a href="http://us.acer.com/ac/en/US/content/group/monitors" target="_blank"><img src="/img/new_window.png" /> Acer</a></td><td>Acer AL1916W</td><td></td></tr><tr><td>Data Collection Monitor</td><td><a href="http://us.acer.com/ac/en/US/content/group/monitors" target="_blank"><img src="/img/new_window.png" /> Acer</a></td><td>Acer AL1916W</td><td></td></tr><tr><td>Participant CRT monitor</td><td><a href="http://www.viewsonic.com/us/" target="_blank"><img src="/img/new_window.png" /> ViewSonic</a></td><td>P810</td><td></td></tr><tr><td>Data processing software</td><td><a href="http://sccn.ucsd.edu/eeglab/" target="_blank"><img src="/img/new_window.png" /> EEGLAB</a></td><td></td><td>Open source (free) software package based in Matlab.</td></tr></tbody></table>

using the threat probability task to assess anxiety and fear during uncertain and certain threat

某些威胁和焦虑不确定威胁的恐惧是不同的情感与独特的行为，认知，注意力和神经解剖学的组件。既焦虑和恐惧可以通过测量惊跳反射的增强作用进行了研究，在实验室。惊跳反射是当一个有机体受到威胁和需要防御很高，得到增强防御反射。惊跳反射是通过肌电图（EMG）的眼轮匝肌进行了简短的，激烈的，声阵阵白噪声（ 即 "不惊人死不休探测器"）的诱发评估。惊吓增效的计算公式为展示套视觉威胁线索的信号传递温和的电击相对于套匹配线索信号没有冲击（无威胁线索）的过程中增加了惊吓反应幅度。在威胁概率任务，怕是通过惊吓增效，以很高的概率（100％扣队伍冲击测量; certai不确定的）威胁线索，n）的威胁线索，而焦虑是通过惊吓增效，以低概率（20％扣队伍冲击测量。惊吓增效的威胁概率任务过程中的测量提供了一个客观的，容易实现的替代方案的评估，通过自我报告或其他方法（ 例如 ，神经影像学检查），可能是不恰当的或不切实际的一些研究人员的负面影响。惊吓增效经过严格的研究在动物（ 例如 ，啮齿动物，非人类灵长类动物）和人类这有利于动物到人类的转化研究。在确定与不确定的威胁惊吓增效提供了一个客观的衡量消极的情感和独特的情感状态（恐惧，焦虑），以研究在精神病理学，药物使用/滥用和广泛的情感科学使用。因此，它已被广泛兴趣在精神病理病因临床科学家和感兴趣的INDIVI情感科学家双重差异的情感。

威胁概率任务均为100％（某些）概率和20％（不确定）的概率威胁线索（ 图6B）时会产生强大的惊吓增效。不确定的（20％）威胁状况时使用此任务显示惊吓增效以前的结果，以上述概率高（100％）（一定的）威胁状况时的惊吓增效来显著增加。温和急性给药确实酒精（目标的0.08％血液中的酒精浓度）产生的惊吓增效过程中20％（不确定）的威胁与100％的（特定）威胁更大的选择性降?...

Watch this Scientific Journal Video about Using the Threat Probability Task to Assess Anxiety and Fear During Uncertain and Certain Threat at JoVE.com

Using the Threat Probability Task to Assess Anxiety and Fear During Uncertain and Certain Threat

Potentiation of the startle reflex is measured via electromyography of the orbicularis oculi muscle during low (uncertain) and high (certain) probability electric shock threat in the Threat Probability Task. This provides an objective measure of distinct negative emotional states (fear/anxiety) for research on psychopathology, substance use/abuse, and broad affective science.

使用威胁概率任务，以评估焦虑和恐惧在不确定性和一定的威胁

Fear of certain threat and anxiety about uncertain threat are distinct emotions with unique behavioral, cognitive-attentional, and neuroanatomical ...

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Research

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15.2K 次观看.  University of Wisconsin-Madison. Potentiation of the startle reflex is measured via electromyography of the orbicularis oculi muscle during low (uncertain) and high (certain) probability electric shock threat in the Threat Probability Task. This provides an objective measure of distinct negative emotional states (fear/anxiety) for research on psychopathology, substance use/abuse, and broad affective science. 

视频: Using the Threat Probability Task to Assess Anxiety and Fear During Uncertain and Certain Threat

Disrupting Reconsolidation of Fear Memory in Humans by a Noradrenergic &#946;-Blocker

The basic design used in our human fear-conditioning studies on disrupting reconsolidation includes testing over different phases across three consecutive days. On day 1 - the fear acquisition phase, healthy participants are exposed to a series of picture presentations. One picture stimulus (CS1+) is repeatedly paired with an aversive electric stimulus (US), resulting in the acquisition of a fear association, whereas another picture stimulus (CS2-) is never followed by an US. On day 2 - the memory reactivation phase, the participants are re-exposed to the conditioned stimulus without the US (CS1-), which typically triggers a conditioned fear response. After the memory reactivation we administer an oral dose of 40 mg of propranolol HCl, a &#946;-adrenergic receptor antagonist that indirectly targets the protein synthesis required for reconsolidation by inhibiting the noradrenaline-stimulated CREB phosphorylation. On day 3 - the test phase, the participants are again exposed to the unreinforced conditioned stimuli (CS1- and CS2-) in order to measure the fear-reducing effect of the manipulation. This retention test is followed by an extinction procedure and the presentation of situational triggers to test for the return of fear. Potentiation of the eye blink startle reflex is measured as an index for conditioned fear responding. Declarative knowledge of the fear association is measured through online US expectancy ratings during each CS presentation. In contrast to extinction learning, disrupting reconsolidation targets the original fear memory thereby preventing the return of fear. Although the clinical applications are still in their infancy, disrupting reconsolidation of fear memory seems to be a promising new technique with the prospect to persistently dampen the expression of fear memory in patients suffering from anxiety disorders and other psychiatric disorders.

Disrupting reconsolidation is a promising approach to dampen the behavioral expression of fear memory in patients with anxiety disorders or posttraumatic stress disorder. In a series of human fear conditioning studies we showed that disrupting reconsolidation by the noradrenergic &#946;-blocker propranolol is very effective in erasing conditioned fear responding.

由去甲肾上腺素能β受体阻滞剂破坏恐惧记忆在人类再固结

The basic design used in our human fear-conditioning studies on disrupting reconsolidation includes testing over different phases across three consecutive ...

科研

行为学

Measuring Attentional Biases for Threat in Children and Adults

Investigators have long been interested in the human propensity for the rapid detection of threatening stimuli. However, until recently, research in this domain has focused almost exclusively on adult participants, completely ignoring the topic of threat detection over the course of development. One of the biggest reasons for the lack of developmental work in this area is likely the absence of a reliable paradigm that can measure perceptual biases for threat in children. To address this issue, we recently designed a modified visual search paradigm similar to the standard adult paradigm that is appropriate for studying threat detection in preschool-aged participants. Here we describe this new procedure. In the general paradigm, we present participants with matrices of color photographs, and ask them to find and touch a target on the screen. Latency to touch the target is recorded. Using a touch-screen monitor makes the procedure simple and easy, allowing us to collect data in participants ranging from 3 years of age to adults. Thus far, the paradigm has consistently shown that both adults and children detect threatening stimuli (e.g., snakes, spiders, angry/fearful faces) more quickly than neutral stimuli (e.g., flowers, mushrooms, happy/neutral faces). Altogether, this procedure provides an important new tool for researchers interested in studying the development of attentional biases for threat.

Here we describe a touch-screen visual search paradigm that can be used to study threat detection across the lifespan. The paradigm has already been used in various studies demonstrating that both children and adults detect threatening stimuli like snakes, spiders, and angry faces faster than non-threatening stimuli.

测量注意偏向对威胁儿童和成人

Investigators have long been interested in the human propensity for the rapid detection of threatening stimuli. However, until recently, research in this ...

Quantifying Cognitive Decrements Caused by Cranial Radiotherapy

With the exception of survival, cognitive impairment stemming from the clinical management of cancer is a major factor dictating therapeutic outcome. For many patients afflicted with CNS and non-CNS malignancies, radiotherapy and chemotherapy offer the best options for disease control. These treatments however come at a cost, and nearly all cancer survivors (~11 million in the US alone as of 2006) incur some risk for developing cognitive dysfunction, with the most severe cases found in patients subjected to cranial radiotherapy (~200,000/yr) for the control of primary and metastatic brain tumors1. Particularly problematic are pediatric cases, whose long-term survival plagued with marked cognitive decrements results in significant socioeconomic burdens2. To date, there are still no satisfactory solutions to this significant clinical problem.
We have addressed this serious health concern using transplanted stem cells to combat radiation-induced cognitive decline in athymic rats subjected to cranial irradiation3. Details of the stereotaxic irradiation and the in vitro culturing and transplantation of human neural stem cells (hNSCs) can be found in our companion paper (Acharya et al., JoVE reference). Following irradiation and transplantation surgery, rats are then assessed for changes in cognition, grafted cell survival and expression of differentiation-specific markers 1 and 4-months after irradiation. To critically evaluate the success or failure of any potential intervention designed to ameliorate radiation-induced cognitive sequelae, a rigorous series of quantitative cognitive tasks must be performed. To accomplish this, we subject our animals to a suite of cognitive testing paradigms including novel place recognition, water maze, elevated plus maze and fear conditioning, in order to quantify hippocampal and non-hippocampal learning and memory. We have demonstrated the utility of these tests for quantifying specific types of cognitive decrements in irradiated animals, and used them to show that animals engrafted with hNSCs exhibit significant improvements in cognitive function3.
The cognitive benefits derived from engrafted human stem cells suggest that similar strategies may one day provide much needed clinical recourse to cancer survivors suffering from impaired cognition. Accordingly, we have provided written and visual documentation of the critical steps used in our cognitive testing paradigms to facilitate the translation of our promising results into the clinic.

Cognitive impairment resulting from the radiotherapeutic management of brain tumors represents a clinically intractable condition that adversely impacts quality of life. The capability to critically evaluate potential interventions for ameliorating radiation-induced cognitive decrements ultimately depends on the capability to undertake rigorous quantitative assessments of cognition.

量化颅放疗引起的认知递减

With the exception of survival, cognitive impairment stemming from the clinical management of cancer is a major factor dictating therapeutic outcome. For ...

医学

Experimental Research Examining How People Can Cope with Uncertainty Through Soft Haptic Sensations

Human beings are constantly surrounded by uncertainty and change. The question arises how people cope with such uncertainty. To date, most research has focused on the cognitive strategies people adopt to deal with uncertainty. However, especially when uncertainty is due to unpredictable societal events (e.g., economical crises, political revolutions, terrorism threats) of which one is unable to judge the impact on one&#8217;s future live, cognitive strategies (like seeking additional information) is likely to fail to combat uncertainty. Instead, the current paper discusses a method demonstrating that people might deal with uncertainty experientially through soft haptic sensations. More specifically, because touching something soft creates a feeling of comfort and security, people prefer objects with softer as compared to harder properties when feeling uncertain. Seeking for softness is a highly efficient and effective tool to deal with uncertainty as our hands are available at all times. This protocol describes a set of methods demonstrating 1) how environmental (un)certainty can be situationally activated with an experiential priming procedure, 2) that the quality of the softness experience (what type of softness and how it is experienced) matters and 3) how uncertainty can be reduced using different methods.

To date research has focused on cognitive strategies people adopt to cope with uncertainty. This research examines instead an experiential way of dealing with uncertainty and introduces a set of experimental methods showing how the experience of haptic softness can serve as a tool to deal with uncertainty.

实验研究研究如何人能不确定性通过软触觉感知应对

Human beings are constantly surrounded by uncertainty and change. The question arises how people cope with such uncertainty. To date, most research has ...

Investigating the Neural Mechanisms of Aware and Unaware Fear Memory with fMRI

Pavlovian fear conditioning is often used in combination with functional magnetic resonance imaging (fMRI) in humans to investigate the neural substrates of associative learning 1-5. In these studies, it is important to provide behavioral evidence of conditioning to verify that differences in brain activity are learning-related and correlated with human behavior. 
Fear conditioning studies often monitor autonomic responses (e.g. skin conductance response; SCR) as an index of learning and memory 6-8. In addition, other behavioral measures can provide valuable information about the learning process and/or other cognitive functions that influence conditioning. For example, the impact unconditioned stimulus (UCS) expectancies have on the expression of the conditioned response (CR) and unconditioned response (UCR) has been a topic of interest in several recent studies 9-14. SCR and UCS expectancy measures have recently been used in conjunction with fMRI to investigate the neural substrates of aware and unaware fear learning and memory processes 15. Although these cognitive processes can be evaluated to some degree following the conditioning session, post-conditioning assessments cannot measure expectations on a trial-to-trial basis and are susceptible to interference and forgetting, as well as other factors that may distort results 16,17 .
Monitoring autonomic and behavioral responses simultaneously with fMRI provides a mechanism by which the neural substrates that mediate complex relationships between cognitive processes and behavioral/autonomic responses can be assessed. However, monitoring autonomic and behavioral responses in the MRI environment poses a number of practical problems. Specifically, 1) standard behavioral and physiological monitoring equipment is constructed of ferrous material that cannot be safely used near the MRI scanner, 2) when this equipment is placed outside of the MRI scanning chamber, the cables projecting to the subject can carry RF noise that produces artifacts in brain images, 3) artifacts can be produced within the skin conductance signal by switching gradients during scanning, 4) the fMRI signal produced by the motor demands of behavioral responses may need to be distinguished from activity related to the cognitive processes of interest. Each of these issues can be resolved with modifications to the setup of physiological monitoring equipment and additional data analysis procedures. Here we present a methodology to simultaneously monitor autonomic and behavioral responses during fMRI, and demonstrate the use of these methods to investigate aware and unaware memory processes during fear conditioning.

A methodology to investigate the neural mechanisms that support aware and unaware memory processes during fear conditioning is described. This method monitors blood oxygen level dependent (BOLD) functional magnetic resonance imaging, skin conductance response, and unconditioned stimulus expectancy during Pavlovian fear conditioning to assess the neural correlates of distinct memory processes.

调查的意识到，不知道用功能磁共振成像的恐惧记忆的神经机制

Pavlovian fear conditioning is often used in combination with functional magnetic resonance imaging (fMRI) in humans to investigate the neural substrates ...

神经科学

Reducing State Anxiety Using Working Memory Maintenance

The purpose of this protocol is to explain how to examine the relationship between working memory processes and anxiety by combining the Sternberg Working Memory (WM) and the threat of shock paradigms. In the Sternberg WM paradigm, subjects are required to maintain a series of letters in the WM for a brief interval and respond by identifying whether the position of a given letter in the series matches a numerical prompt. In the threat of shock paradigm, subjects are exposed to alternating blocks where they are either at risk of receiving unpredictable presentations of a mild electric shock or are safe from the shock. Anxiety is probed throughout the safe and threat blocks using the acoustic startle reflex, which is potentiated under threat (Anxiety-Potentiated Startle (APS)). By conducting the Sternberg WM paradigm during the threat of shock and probing the startle response during either the WM maintenance interval or the intertrial interval, it is possible to determine the effect of WM maintenance on APS.

This protocol demonstrates how to measure anxiety-potentiated startle during the Sternberg Working Memory paradigm.

使用工作记忆维护降低状态焦虑

The purpose of this protocol is to explain how to examine the relationship between working memory processes and anxiety by combining the Sternberg Working ...

Measuring the Subjective Value of Risky and Ambiguous Options using Experimental Economics and Functional MRI Methods

Most of the choices we make have uncertain consequences. In some cases the probabilities for different possible outcomes are precisely known, a condition termed "risky". In other cases when probabilities cannot be estimated, this is a condition described as "ambiguous". While most people are averse to both risk and ambiguity1,2, the degree of those aversions vary substantially across individuals, such that the subjective value of the same risky or ambiguous option can be very different for different individuals. We combine functional MRI (fMRI) with an experimental economics-based method3 to assess the neural representation of the subjective values of risky and ambiguous options4. This technique can be now used to study these neural representations in different populations, such as different age groups and different patient populations.
In our experiment, subjects make consequential choices between two alternatives while their neural activation is tracked using fMRI. On each trial subjects choose between lotteries that vary in their monetary amount and in either the probability of winning that amount or the ambiguity level associated with winning. Our parametric design allows us to use each individual's choice behavior to estimate their attitudes towards risk and ambiguity, and thus to estimate the subjective values that each option held for them. Another important feature of the design is that the outcome of the chosen lottery is not revealed during the experiment, so that no learning can take place, and thus the ambiguous options remain ambiguous and risk attitudes are stable. Instead, at the end of the scanning session one or few trials are randomly selected and played for real money. Since subjects do not know beforehand which trials will be selected, they must treat each and every trial as if it and it alone was the one trial on which they will be paid. This design ensures that we can estimate the true subjective value of each option to each subject. We then look for areas in the brain whose activation is correlated with the subjective value of risky options and for areas whose activation is correlated with the subjective value of ambiguous options.

Using functional MRI and behavioral methods to determine the neural representation of the subjective value of risky and ambiguous options in the human brain.

，测量主观价值风险和不明确的选项，使用实验经济学和功能磁共振成像的方法

Most of the choices we make have uncertain consequences. In some cases the probabilities for different possible outcomes are precisely known, a condition ...

Stress-Enhanced Fear Learning, a Robust Rodent Model of Post-Traumatic Stress Disorder

Fear behaviors are important for survival, but disproportionately high levels of fear can increase the vulnerability for developing psychiatric disorders such as post-traumatic stress disorder (PTSD). To understand the biological mechanisms of fear dysregulation in PTSD, it is important to start with a valid animal model of the disorder. This protocol describes the methodology required to conduct stress-enhanced fear learning (SEFL) experiments, a preclinical model of PTSD, in both rats and mice. SEFL was developed to recapitulate critical aspects of PTSD, including long-term sensitization of fear learning caused by an acute stressor. SEFL uses aspects of Pavlovian fear conditioning but produces a distinct and robust sensitized fear response far greater than normal conditional fear responses. The trauma procedure involves placing a rodent in a conditioning chamber and administering 15 unsignaled shocks randomly distributed over 90 minutes (for rat experiments; for mouse experiments, 10 unsignaled shocks randomly distributed over 60 minutes are used). On day 2, rodents are placed in a novel conditioning context where they receive a single shock; then, on day 3 they are placed back in the same context as on day 2 and tested for changes in freezing levels. Rodents that previously received the trauma display enhanced levels of freezing on the test day compared to those that received no shocks on the first day. Thus, with this model, a single highly stressful experience (the trauma) produces extreme fear of the stimuli associated with the traumatic event.

Here we describe the detailed methodology required to conduct stress-enhanced fear learning (SEFL) experiments, a preclinical model of post-traumatic stress disorder, in both rats and mice. The model utilizes aspects of Pavlovian fear conditioning and freezing as an index of enhanced fear in rodents.

压力增强恐惧学习--创伤后应激障碍的健壮啮齿动物模型

Fear behaviors are important for survival, but disproportionately high levels of fear can increase the vulnerability for developing psychiatric disorders ...

An Inescapable Cat Odor Exposure Protocol for Studying Innate and Contextual Threat Conditioning in Rats

Animals respond to threatening situations by exhibiting a number of defensive behaviors, including avoidance, freezing, and risk assessment. An animal model with an ethological approach offers a deeper insight into the biological mechanisms underlying threat responses. This paper describes a methodology to measure defensive behaviors toward both innate and learned aversive stimuli in rats. Animals were individually exposed to predator odor in an inescapable chamber to elicit a measurable, sustained, defensive state. The experimental design involved placing a rat in a familiar chamber for 10 min followed by exposure to cat odor for another 10 min in the same context. The next day, the rats were re-exposed for 10 min to the same context chamber where cat odor exposure occurred. Sessions were video-recorded and defensive behaviors were assessed on both days. 
The behavioral test was coupled with reversible functional inactivation and c-Fos immunohistochemistry techniques to determine the role of the interoceptive cortex in threat responses. Rats exposed to cat odor on the first day and re-exposed to the context chamber on the second day displayed higher levels of defensive behaviors, and that cat odor elicited a robust increase in the neural activity of the interoceptive cortex. Moreover, muscimol inactivation of the interoceptive cortex reduced the expression of defensive behaviors in response to cat odor and impaired contextual threat memory. These results show that this behavioral assay is a useful tool for studying neural mechanisms of defensive behaviors and may offer insight into mechanisms that mediate fear in humans and its related disorders.

<meta charset="utf8"></head><body>一种不可避免的猫气味暴露方案，用于研究大鼠先天性和情境威胁条件反射

Cat skin/fur odor exposure provides a reliable method to investigate neural circuits and mechanisms of defensive responses in rodents and may offer insight into mechanisms that mediate fear in humans. Here, we describe a protocol for investigating the role of the interoceptive cortex in threat responses in rats.

一种不可避免的猫气味暴露方案，用于研究大鼠先天性和情境威胁条件反射

Animals respond to threatening situations by exhibiting a number of defensive behaviors, including avoidance, freezing, and risk assessment. An animal ...

使用威胁概率任务，以评估焦虑和恐惧在不确定性和一定的威胁

摘要

探索更多视频

由去甲肾上腺素能β受体阻滞剂破坏恐惧记忆在人类再固结

测量注意偏向对威胁儿童和成人

量化颅放疗引起的认知递减

实验研究研究如何人能不确定性通过软触觉感知应对

调查的意识到，不知道用功能磁共振成像的恐惧记忆的神经机制

使用工作记忆维护降低状态焦虑

，测量主观价值风险和不明确的选项，使用实验经济学和功能磁共振成像的方法

压力增强恐惧学习--创伤后应激障碍的健壮啮齿动物模型

一种不可避免的猫气味暴露方案，用于研究大鼠先天性和情境威胁条件反射

一种不可避免的猫气味暴露方案，用于研究大鼠先天性和情境威胁条件反射