Electrocorticographic studies of human cortical function

描述(改编自申请人的摘要)： 拟议的研究是识别和验证电生理信号 并用它们来研究人类大脑皮质加工的神经机制 运动、感觉和语言功能。之前的脑电和脑磁图研究表明 脑区皮质激活与脑电活动相关的能量变化有关 阿尔法(8-13赫兹)和伽马(40赫兹)振荡。使用皮质脑电图仪 用于临床的硬膜下电极(ECOG)记录，我们 证实了这些观测结果，并发现了一个与事件相关的宽带 在高伽马频率(80-100赫兹)时功率增大。这一新颖的索引 皮质激活的功能在空间和时间上更加离散地局部化， 与功能解剖学和神经生理学(ERP)更一致 相互关联，而不是先前描述的光谱变化。伽马振荡有 与大脑皮层神经元组件的同步化有关 正在处理。相反，人们认为会出现对阿尔法振荡的抑制 从丘脑皮质回路的激活，否则门皮质 正在处理。因此，我们建议检验以下假设：(1) 宽带“高”伽马ERS指标特定于任务的皮质处理， (2)阿尔法去同步化通过丘脑皮质促进这一过程 电路。我们的具体目标是测试(A)空间和(B) 皮质激活的这些光谱指数之间的时间对应关系 和以下基准：(I)功能解剖学的一般知识 知觉、运动和语言任务，(Ii)特定的功能解剖 从用于临床目的的皮质刺激标测中获得的信息， (3)知觉刺激和运动反应的潜伏期和持续时间；以及 (4)事件相关电位的时空特性。这个 我们从这些ECoG研究得出的结论的概括性将在 正常受试组采用高密度头皮脑电。信息源自 这一研究将为今后神经生理学的研究提供便利。 人脑激活的相关性，包括对时间和时间的研究 正常和紊乱的认知/神经元操作的地形图。

DESCRIPTION(adapted from applicant's abstract): The overall objective of the proposed research is to identify and validate electrophysiological signatures of human cortical processing and to use them to study the neural mechanisms of motor, sensory, arid language functions. Previous EEG and MEG studies have linked regional cortical activation with event-related changes in the energy of alpha (8-13 Hz) and gamma (40 Hz) oscillations. Using electrocorticographic (ECoG) recordings from subdural electrodes implanted for clinical purposes, we have confirmed these observations and discovered an event-related broad-band augmentation of power in high gamma frequencies (80-100 Hz). This novel index of function cortical activation is more discretely localized in space and time, and more consistent with functional-anatomic and neurophysiological (ERP) correlates, than previously described spectral changes. Gamma oscillations have been associated with the synchronization of neuronal assemblies during cortical processing. In contrast, suppression of alpha oscillations is thought to arise from the activation of thalamocortical circuits that otherwise gate cortical processing. We therefore propose to test the following hypotheses: (1) that broad-band "high" gamma ERS indexes task-specific cortical processing, and that (2) alpha desynchronization facilitates this processing via thalamocortical circuits. Our specific aims are directed toward testing the (A) spatial and (B) temporal correspondence between these spectral indices of cortical activation and the following benchmarks: (i) general knowledge of the functional anatomy of perceptual, motor, and language tasks, (ii) specific functional-anatomic information derived from cortical stimulation mapping for clinical purposes, (iii) the latency and duration of perceptual stimuli and motor responses, and (iv) spatiotemporal properties of event-related potentials. The generalizability of our conclusions from these ECoG studies will be tested in a group of normal subjects using high density scalp EEG. Information derived from this research will facilitate future investigations of the neurophysiological correlates of human brain activation, including studies of the timing and topography of normal and disordered cognitive/neuronal operations.