HOW INHIBITORY CONTROL MODIFIES STIMULUS VALUE AND MOTIVATION

描述(申请人提供)：日常的自我控制行为，例如，香烟、食物和赌博，部分取决于阻止行动的能力。虽然关于人类停止行动的了解很多，但现实世界中的自我控制，就像上面的例子一样，具有很强的估值或动机成分。然而，关于停车与价值/动机如何相互作用的研究很少。我们的核心假设是，基于初步数据，停车会降低价值和动机。我们将在三种停车系统的基础上测试三种可能的机制。我们的第一个目标是测试快速停止如何同时降低刺激价值。我们假设，快速停止招募了一个全局停止系统，该系统禁止所有当前活跃的表示，包括值。要测试这一点，需要测量全局抑制(使用经颅磁刺激，TMS)，对停止系统和价值表示进行成像(使用功能磁共振成像和皮层脑电图术)，最重要的是，显示大脑中对停止至关重要的区域对降低价值具有重要意义(使用 新形式的直接电刺激，在人类中)。我们的第二个目标是研究产生行动倾向的动机刺激是如何被抑制的。我们的假设是，这是由选择性停止系统完成的，该系统是根据受试者在工作记忆中的目标建立的，可以由动机刺激本身触发。我们将通过使用TMS测量运动激活和抑制的时间动力学来测试这一点，并使用功能磁共振成像来检查假定的潜在的额纹状体系统。我们的第三个目标是利用自动停止来降低刺激价值和动机。我们假设，反复停止(通过训练)会产生刺激停止标记，因此当该刺激在未来发生时，它会(自动)重新激活停止系统，从而降低刺激价值和动机。

DESCRIPTION (provided by applicant): Everyday acts of self-control directed at, for example, cigarettes, food, and gambling, depend, in part, on the ability to stop action. While much is known about action stopping in humans, real world self-control, as in the above examples, has a strong valuational or motivational component. Yet there is scant research on how motor stopping interacts with value/motivation. Our core hypothesis, based on preliminary data, is that motor stopping can reduce value and motivation. We will test three possible mechanisms based on our work with three kinds of stopping systems. Our first aim is to test how rapid stopping concurrently reduces stimulus value. We hypothesize that rapid stopping recruits a global stopping system that inhibits all currently active representations, including value. Testing this requires measuring global inhibition (with Transcranial Magnetic Stimulation, TMS), imaging the stopping system and value representations (with fMRI and Electrocorticography) and, above all, showing that brain regions critical for stopping are causally important for reducing value (using a novel form of Direct Electrical Stimulation, in humans). Our second aim is to examine how motivational stimuli, which generate action tendencies, are suppressed. Our hypothesis is that this is done by the selective stopping system that is set up according to a subject's goals in working memory and which can be triggered by the motivational stimulus itself. We will test this by measuring the temporal dynamics of motor activation and suppression with TMS, and using fMRI to examine the putative underlying fronto-striatal system. Our third aim is to leverage automatic stopping to reduce stimulus value and motivation. We hypothesize that repeated stopping (via training) generates stimulus stop-tag, so that when that stimulus occurs in the future it reactivates the stopping system (automatically), which then reduces stimulus value and motivation.