Concurrent EEG and fMRI Studies in Human Brain Activity

描述(由申请人提供)： 初步研究表明，通过结合功能磁共振成像(FMRI)的高空间分辨率(毫米)和脑电(EEG)的高时间分辨率(毫秒)，有可能获得大脑活动的非侵入性时空图，例如皮质信息交换、觉醒和警觉性的变化，或癫痫发作，但不能随着时间的推移精确重现性。虽然fMRI和EEG的单独测量在某些情况下已经足够，但涉及学习或启动的认知实验需要同时测量。我们建议使用我们一直在开发的技术来建立一种医疗设备，使同时进行的脑电和功能磁共振成像记录能够安全和准确地获得。初步结果表明，在存在脑电电极和导线的情况下，受试者组织中的MRI射频(RF)场所消耗的功率大大增加。建议的仪器将最大限度地减少射频场的相互作用，以提高受试者的安全性和fMRI记录的质量。该仪器还将包括一种新的时变自适应噪声消除方案，以减少脑电中存在的伪影噪声。用于并行EEG/fMRI的仪器将使用稳态EEG、视觉诱发电位(VEP)和事件相关电位(ERP)实验方案进行测试。事件相关电位(ERPs)是与感觉、认知和运动事件一起诱发的小相电位，可通过头皮电极记录检测到。虽然各种事件相关电位的波幅和潜伏期已经被脑电广泛研究，但潜在来源的位置在很大程度上仍然是未知的。我们提出了一系列同步的fMRI/EEG实验，以研究人类大脑中事件相关电位的空间位置和时间处理。

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.