DEVELOPMENT OF LOW FREQUENCY MEG HARDWARE AND SOFTWARE

描述(改编自申请者摘要)：总体目标 建议的研究是开发硬件、软件和技术来 大大扩展脑磁图(MEG)的用途，既作为一种 临床诊断工具和作为基础研究的一种方式 神经科学。研究的目的之一是开发新的分析方法 利用MEG的独特能力提取更多的技术和软件 来自生理性磁场的重要信息种类 并使这些技术易于使用。解决问题的有效方法 区分和定位几乎点火的弱发电机 同时，申请者已经开发出了更强大的技术。AS 作为这些技术及其可转移性的演示，它是 建议研究阅读障碍患者听觉诱发反应的异常 个人。已经开发出一种方法来监测细微的光谱变化 脑磁图中伴随警觉性或觉醒变化的信号 比常规的睡眠分期进行量化分类。这 将改进技术并将其应用于自发脑磁图的分析 偏头痛期间的活动。Meg的第二个功能是 已知的非常慢(DC)漂移的完全非侵入性测量 在各种病理条件下出现。这样的转变不可能 易于使用表面脑电(EEC)进行研究，因为 不可避免地发生在电极-蒙皮界面的阻抗变化。 不幸的是，脑磁图的测量也受到噪声的污染，两者 环境(即使在精心屏蔽的房间里)和 病人的身体没有在研究中，这是一个严重的观察问题 自发的低频活动。提供噪音消除技术 神经磁力仪制造商已经证明不足以处理这样的问题 问题，在某些情况下，它们自己将构件引入数据。 涉及噪声的噪声消除技术的重大进展 进行了模式识别。在测量方面也取得了进展 直流磁场的绝对值，例如预期从 损伤的电流和蔓延的皮质抑制。这些技术 将应用于偏头痛患者自发脑磁图活动的研究 在癫痫手术患者和癫痫大鼠模型中，两者都是如此 其中损伤电流的野将在手术前和术后进行研究。 在脑磁图信号的数学建模方面取得了有益的进展 传播性皮质抑制(SCD)和为研究创建体模 出现在SCD中的电阻率的几率。

DESCRIPTION (Adapted from Applicant's Abstract): The overall objective of the proposed research is to develop hardware, software, and techniques to substantially expand the utility of Magnetoencephalography (MEG), both as a clinical diagnostic tool and as a modality for basic studies in the neurosciences. One aim of the research is to develop new analytical techniques and software to exploit the unique ability of MEG to extract more significant kinds of information from magnetic fields of physiologic origin and to make these techniques readily usable. Effective methods for distinguishing and localizing weak generators which fire almost simultaneously with stronger ones have been developed by the applicants. As a demonstration of these techniques and of their transferability, it is proposed to study anomalies in the auditory evoked responses of dyslexic individuals. A method has been developed to monitor subtle spectral changes in MEG signals accompanying changes in alertness or arousal which is more quantitative than the conventional sleep stage classification. This technique will be refined and applied to the analysis of spontaneous MEG activity during migraine headache. A second capability of MEG is the completely non-invasive measurement of very slow (DC) shifts which are known to arise in a variety of pathological conditions. Such shifts cannot readily be studied using surface electroencephalography (EEC) because of impedance changes which inevitably occur at the electrode-skin interface. Unfortunately, MEG measurements are also contaminated by noise, both environmental (even in elaborately shielded rooms) and from regions of the patient's body not under study, a serious problem for the observation of spontaneous low frequency activity. Noise cancellation techniques provided by neuromagnetometer manufacturers have proven inadequate to deal with such problems, in some cases themselves introducing artifacts into the data. Significant progress in noise cancellation techniques involving noise pattern recognition has been made. Progress has also been made in measuring absolute values of DC magnetic fields, such as are expected to arise from currents of injury and from spreading cortical depression. These techniques will be applied to studies of spontaneous MEG activity in migraine patients and in epilepsy surgery patients as well as a rat model of epilepsy, in both of which fields due to injury currents will be studied pre and post surgery. Useful progress has been made in mathematical modeling of MEG signals from spreading cortical depression (SCD) and in creating a phantom for the study of resistivity chances such as occur in SCD.