Event-related EEG time-frequency analysis: An overview of measures and an analysis of early gamma band phase locking in schizophrenia
Event-related EEG time-frequency analysis: An overview of measures and an analysis of early gamma band phase locking in schizophrenia
复制标题
DOI：
10.1093/schbul/sbn093
复制
发表时间：
2008-09-01
影响因子：
6.6
通讯作者：
Mathalon, Daniel H.
中科院分区：
文献类型：
--
作者：
Roach, Brian J.;Mathalon, Daniel H.
越来越多的精神分裂症研究一直在使用时频分析来检查脑电(EEG)数据，记录与疾病相关的神经元振荡异常及其同步，特别是在伽马频段。本文综述了脑电频谱分解的常用方法、时频分析、从脑电信号中分别量化幅度和相位信息的测量类型，以及参数选择对分析结果的影响。然后，我们比较了22名健康对照组和21名患有精神分裂症的药物患者在呈现标准音调后约50毫秒诱发的伽马频段(36-50赫兹)反应的锁相程度(即锁相因子)。这些音调是受试者执行的一项奇怪的听觉任务的一部分，同时从他们的头皮上记录脑电。结果显示，在健康对照组中，在音调开始后20到60毫秒之间，额部电极上显著的伽马频段相位锁定，而在精神分裂症患者中，这种锁定显著减少(P=0.03)。这一发现表明，精神分裂症患者对听觉刺激的早期诱发伽马波段反应缺乏同步性。我们从损害精神分裂症事件相关伽马阶段同步性的病理生理机制的角度讨论了这一结果，并进一步试图将这一发现与先前未能发现这一影响的研究相一致。
An increasing number of schizophrenia studies have been examining electroencephalography (EEG) data using time-frequency analysis, documenting illness-related abnormalities in neuronal oscillations and their synchronization, particularly in the gamma band. In this article, we review common methods of spectral decomposition of EEG, time-frequency analyses, types of measures that separately quantify magnitude and phase information from the EEG, and the influence of parameter choices on the analysis results. We then compare the degree of phase locking (ie, phase-locking factor) of the gamma band (36-50 Hz) response evoked about 50 milliseconds following the presentation of standard tones in 22 healthy controls and 21 medicated patients with schizophrenia. These tones were presented as part of an auditory oddball task performed by subjects while EEG was recorded from their scalps. The results showed prominent gamma band phase locking at frontal electrodes between 20 and 60 milliseconds following tone onset in healthy controls that was significantly reduced in patients with schizophrenia (P = .03). The finding suggests that the early-evoked gamma band response to auditory stimuli is deficiently synchronized in schizophrenia. We discuss the results in terms of pathophysiological mechanisms compromising event-related gamma phase synchrony in schizophrenia and further attempt to reconcile this finding with prior studies that failed to find this effect.