Project 5 The causal role of neocortical beta events in human sensory perception

β节律(15-29赫兹)是非侵入性测量的最主要的大脑信号之一，在患有 脑磁图和脑电图仪(MEG/EEG)。它们是知觉和运动的有力预测者 表现，并在疾病状态下中断，如帕金森氏症。然而，贝塔在功能中的因果作用 仍然是未知的。在这个方案中，我们将结合人类脑电、经颅磁刺激(TMS)和 生物物理学原理神经模型研究β和知觉之间的直接因果关系 并定义对感知产生最佳影响的新的TMS范例。 我们先前的研究表明，用脑磁图测量人类初级脑组织中刺激前β活动 躯体感觉皮层(SI)“抑制”触觉检测，从而使平均刺激前β能力越高 受试者检测到手指受到阈值轻拍的可能性就越小。此外，平均贝塔功率在 无人参与的区域，大概是作为过滤分散注意力的信息以促进感知的一种手段(Jones et 艾尔·J·神经西。2010)。最近，我们报道了高能量的Beta活动以短暂的“事件”出现 (&lt；150ms)，主峰持续一个测试期约40-60ms(Sherman等人PNAS 2016)。初步数据表明，这种贝塔事件是间歇性的，贝塔事件的发生率是 贝塔的转变与注意力和对感知的影响。在参与的人中，刺激前Beta事件的发生率降低，并且 无人看管的躯体主题区域(分心区域)的增加，对应于更高的概率 侦测。 我们预测当触觉刺激被抑制时，注意部位的触觉刺激的检测将被抑制 在相应的躯体定位区域中自发脑电β事件发生率较高后交付，以及 在无人参与的躯体病变区(面积)高β事件发生率后交付时增强 分心)(目标1)。我们进一步预测，模拟内源性Beta事件模式的TMS协议将影响 感知比非TMS条件和标准的功能抑制TMS协议(AIM)更有效 2)。我们小组专门设计的计算神经模型将模拟宏观尺度的EEG信号 用于解释观测数据背后的电路机制(目标3)。 好了！

Beta rhythms (15-29 Hz) are one of the most dominant brain signals measured non-invasively in humans with magento- and electro-encephalography (MEG/EEG). They are strong predictors of perception and motor performance, and disrupted in disease states, such as Parkinson’s Disease. Yet, beta’s causal role in function is still unknown. In this proposal, we will combine human EEG, transcranial magnetic stimulation (TMS) and biophysically principled neural modeling to investigate a direct causal relationship between beta and perception and to define novel TMS paradigms that optimally impact perception. Our prior studies have shown that prestimulus beta activity measured with MEG in human primary somatosensory cortex (SI) “inhibits” tactile detection, such that the higher the averaged prestimulus beta power the less likely the subject detects a threshold level tap to the finger. Further, averaged beta power increases in non-attended regions, presumably as a means to filter distracting information to facilitate perception (Jones et al J. Neurosci. 2010). More recently, we reported that that high power beta activity emerges as brief “events” (<150ms) in unaveraged data, with a dominant peak lasting one beta period ~40-60ms (Sherman et al PNAS 2016). Preliminary data suggests such beta events are intermittent and that the rate of beta events underlies beta’s shift with attention and impact on perception. Prestimulus beta event rates decrease in attended, and increase in non-attended somatotopic regions (areas of distraction), corresponding with a higher probability of detection. We predict detection of tactile stimulation in an attended location will be inhibited when tactile stimulation is delivered after high spontaneous EEG beta event rates in the corresponding somatotopic region, and enhanced when delivered after high beta event rates in the non-attended somatotopic region (area of distraction) (Aim 1). We further predict TMS protocols that mimic endogenous beta event patterns will impact perception more effectively than non-TMS conditions and standard functionally “inhibitory” TMS protocols (Aim 2). Computational neural modeling specifically designed by our group to simulate macro-scale EEG signals will be used to intepret circuit mechanisms underlying observed data (Aim 3). !