Quantitative Electrical Measure of Brain Injury

描述（由申请人提供）：在关于大脑对损伤的反应的基础和临床研究中，来自大脑的皮质电信号，即EEG，可用于提供功能障碍的即时指示。因此，我们假设，定量脑电图将是一个强大的工具，对脑损伤的基础研究，并最终，临床诊断。提出了一种基于多分辨小波熵（MRWE）的脑损伤早期反应分析方法。由于恢复脑节律的损伤发生在不同的阶段，涉及过渡的节奏活动在不同的频带，我们建议监测和量化的熵的变化，发生在每个临床频带。我们假设：a）在全脑缺血性脑损伤后，EEG的时域熵将形成损伤水平的敏感指标，并且每个临床频带中EEG的MRWE将识别与缺血后即刻恢复期EEG的爆发特征相关的特征，以及B）从皮层场电位导出的相应熵测量将具有细胞起源（神经元的放电模式）在大脑的皮层和皮层下区域。为了探索这些假说并为脑损伤的实验研究开发严格的理论工具，我们提出：1：理论- a）导出时域熵测量，以监测全脑缺血性脑损伤后EEG的恢复进展。B）导出基于MRWE的分割过程，以识别在缺血后恢复的早期阶段期间看到的初始突发EEG的特征。第二章：实验-通过微电极方法使用实验性单单位和多单位记录，表明源自皮层场电位的不同水平的MRWE反映了丘脑和皮层中神经元群体的缺血后节律活动的过渡阶段。该项目的意义主要在于开发一种新的定量工具，可以使研究脑损伤的基础和临床科学家受益。

DESCRIPTION (provided by applicant): In the basic and clinical research on brain's response to injury, cortical electrical signals from the brain, namely EEG, may be useful in providing an immediate indication of the dysfunction. As such, we hypothesize that quantitative EEG would be a powerful tool for basic research on brain injury and, eventually, clinical diagnosis. A novel approach to analyzing brain's early response to injury, based on the method of "multiresolution wavelet entropy (MRWE)" is proposed. Since the recovery of brain rhythms in response to injury occurs in different stages involving transition of rhythmic activities in different frequency bands, we propose to monitor and quantify the variations in entropy that occur within each clinical band. We hypothesize that a) following global ischemic brain injury, the time domain entropy of EEG would form a sensitive indicator of the level of injury and that the MRWE of EEG in each clinical band would identify features related to the bursting characteristics of EEG in the immediate post-ischemic recovery periods, and b) the corresponding entropy measure derived from the cortical field potentials would have cellular origins (firing pattern of neurons) in cortical and subcortical areas of the brain. To explore these hypotheses and to develop rigorous theoretical tools for experimental studies on brain injury, we propose: 1: Theory - a) Derive a time domain entropy measure with a view to monitor the progress of recovery of EEG following global ischemic brain injury. b) Derive an MRWE-based segmentation procedure to identify the characteristics of initial bursting EEG, seen during early phases of post-ischemic recovery. 2: Experiments - Using experimental single and multi-unit recording by the microelectrode method, show that the varying levels of MRWE derived from the cortical field potentials reflect the transitional stages of post-ischemic rhythmic activity of neuronal population in the thalamus and the cortex. The significance of this project primarily lies in developing a novel quantitative tool that can benefit basic and clinical scientists studying brain injury.