Quantitative Electrical Measure of Brain Injury

描述（由申请人提供）：在脑损伤反应的基础和临床研究中，来自大脑的皮层电信号，即脑电图，可能有助于提供功能障碍的即时指示。因此，我们假设定量脑电图将成为脑损伤基础研究和最终临床诊断的有力工具。提出了一种基于“多分辨率小波熵”的脑损伤早期反应分析方法。由于脑节律在损伤后的恢复发生在不同的阶段，涉及不同频带节律活动的转变，我们建议监测和量化每个临床频带内发生的熵变化。我们假设：a)全脑缺血性损伤后，脑电时域熵可作为损伤程度的敏感指标，脑电各临床波段的核磁共振可识别脑电在缺血恢复后立即爆发的特征；b)从皮层场电位得到的相应熵测度可能在大脑皮层和皮层下区域有细胞起源（神经元的放电模式）。为了探索这些假设，并为脑损伤的实验研究提供严谨的理论工具，我们提出：1 .理论- a)推导时域熵测度，以监测全脑缺血性损伤后脑电恢复的进展。b)推导基于mrwe的分割程序，以识别缺血恢复早期阶段的初始爆发脑电图特征。2：实验-通过微电极方法的单单元和多单元实验记录，表明皮层场电位产生的不同水平的MRWE反映了丘脑和皮层神经元群缺血后节律性活动的过渡阶段。该项目的意义主要在于开发一种新的定量工具，可以使基础和临床科学家研究脑损伤。

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.