Concurrent EEG and fMRI Studies in Human Brain Activity

描述（由申请人提供）： 初步研究表明，通过结合高空间分辨率脑电描记术（EEG）的高时间分辨率（毫秒）与功能性磁共振成像（fMRI）的高时间分辨率（毫米）相结合，可以获得脑活动的非侵入性时空图。内在脑活动，如皮层信息交换、唤醒和警觉性的变化或癫痫尖峰，不适合随时间精确再现。虽然单独测量功能磁共振成像和脑电图是足够的某些情况下，认知实验涉及学习或启动需要同时测量。我们建议使用我们一直在开发的技术来构建一种医疗设备，该设备将允许安全准确地同时获得EEG和fMRI记录。初步结果表明，在EEG电极和导线的存在下，受试者组织中MRI射频（RF）场耗散的功率大大增加。所提出的仪器将最大限度地减少射频场相互作用，以提高受试者安全性和fMRI记录质量。拟议的仪器还将包括一个新的时变自适应噪声消除方案，以减少EEG上的伪影噪声。将使用稳态EEG、视觉诱发电位（VEP）和事件相关电位（ERP）实验方案对同步EEG/fMRI仪器进行测试。事件相关电位（ERP）是与感觉、认知和运动事件相关的小相位电位，可以通过头皮电极记录来检测。虽然各种ERPs的振幅和潜伏期已被广泛研究与EEG，潜在的来源的位置仍然在很大程度上是未知的。我们提出了一系列的同步fMRI/EEG实验，将调查的空间位置和时间处理的事件相关电位在人脑中。

DESCRIPTION (provided by applicant): Preliminary studies suggest that by combining the high spatial resolution (millimeters) of functional magnetic resonance imaging (fMRI) with the high temporal resolution (milliseconds) of electroencephalography (EEG) it is possible to obtain noninvasive spatiotemporal maps of cerebral activitylntrinsic brain activity, such as cortical information exchange, changes in arousal and alertness, or epileptic spiking, is not amenable to precise reproducibility over time. Although separate measurements of fMRI and EEG are adequate for some situations, cognitive experiments involving learning or priming require concurrent measurements. We propose to use techniques we have been developing to build a medical device that will allow concurrent EEG and fMRI recordings to be obtained safely and accurately. Preliminary results show that the power dissipated by the MRI radio frequency (RF) fields in the subject's tissue greatly increases in the presence of EEG electrodes and leads. The proposed instrumentation will minimize the RF fields interaction to improve both subject safety and quality of the fMRI recordings. The proposed instrument will also include a new time varying adaptive noise cancellation scheme to reduce artifact noise present on the EEG. Instrumentation for concurrent EEG/fMRI will be tested using steady-state EEG, visual evoked potential (VEP), and event-related potential (ERP) experimental protocols. Event-related potentials (ERPs) are small phasic potentials elicited in conjunction with sensory, cognitive, and motor events that can be detected by recording from scalp electrodes. Although the amplitude and latency of various ERPs have been extensively studied with EEG, the location of the potential sources remains largely unknown. We propose a series of simultaneous fMRI/EEG experiments that will investigate the spatial location and temporal processing of event-related potentials in the human brain.