Remote Modulation of Reward Circuits with Noninvasive Brain Stimulation

项目摘要 我们的行为与广泛的奖励密不可分，从经济激励（例如，货币 补偿）到社会激励（例如，来自同行的赞美）。接受奖励促进学习，唤起 愉悦感，并增加纹状体内的大脑活动--纹状体是奖赏回路中的一个关键结构。虽然 纹状体对奖励的反应与学习和积极情绪相关，但仍不清楚纹状体对奖励的反应是如何产生的。 人类的奖赏体验与纹状体有因果关系。事实上，纹状体深埋在 这使得通过非侵入性脑刺激评估因果关系的方法无法实现。的 这个项目的目标是确定纹状体内的奖励相关反应是否可以通过 刺激施加到皮层连接。我们将使用一种新型的非侵入性神经调节， 创造了短期经颅交流电刺激（st-tACS）到前额皮质，而参与者 参与可靠地唤起纹状体内激活的奖励任务。我们将讨论两个具体目标。在 我们的第一个目标是研究st-tACS是否会改变纹状体对奖励和相关快乐的反应 一个简单的猜谜游戏。在我们的第二个目标中，我们将研究st-tACS是否改变纹状体反应 奖励和学习。我们假设st-tACS应用于前额叶皮层会增加纹状体的 对奖励的反应，这种效果将与增加快乐（目标1）和增加学习（目标2）联系在一起。 因此，这些发现将在人类纹状体和奖励之间建立因果关系。此外，委员会认为， 人类纹状体的远程调制可以扩展非侵入性脑刺激的范围 方法，可能为精神病理学的新治疗方向奠定基础 以对奖赏的异常反应为特点。

Project Summary Our behavior is inextricably linked to a wide range of rewards, from economic incentives (e.g., monetary compensation) to social incentives (e.g., praise from a peer). Receipt of reward promotes learning, evokes pleasure, and increases brain activity within the striatum—a key structure within the reward circuit. Although striatal responses to reward are correlated with learning and positive emotions, it remains unclear how the experience of reward in humans is causally linked to the striatum. Indeed, the striatum is buried deep inside the brain, making it inaccessible to approaches that assess causality via noninvasive brain stimulation. The goal of this project is to determine whether reward-related responses within the striatum can be influenced via stimulation applied to cortical connections. We will use a novel form of noninvasive neuromodulation, that we coined short-term transcranial alternating current stimulation (st-tACS) to prefrontal cortex while participants engage in reward tasks that reliably evoke activation within the striatum. We will address two specific aims. In our first aim, we will investigate whether st-tACS alters striatal responses to reward and pleasure associated with a simple guessing game. In our second aim, we will investigate whether st-tACS alters striatal responses to reward and learning. We hypothesize that st-tACS applied to prefrontal cortex will increase striatal responses to reward, an effect that will be tied to increased pleasure (Aim 1) and increased learning (Aim 2). These findings would therefore establish causal links between the human striatum and reward. Moreover, remote modulation of the human striatum could expand the purview of noninvasive brain stimulation approaches, potentially establishing a foundation for new therapeutic directions for psychopathologies characterized by aberrant responses to reward.