Investigation of neurophysiological characteristics and its changes after donepezil hydrochloride treatment on mild Alzheimer's disease using EEG spatial analyses

使用GFP、LORETA、Global components和Microstate分析阐明17名轻度阿尔茨海默病患者（AD）（73.6±5.5岁）和17名正常受试者（对照组）（70.3±8.9岁）的神经生理学特征。FAST 4期定义为“轻度”。第二部分观察了3例AD患者服用盐酸多奈哌齐5 mg前后3个月的脑电变化。从19个头皮部位记录闭眼静息EEG（10/20系统）AD在δ频带（1.5-6 Hz）中显示出比对照更高的GFP。LORETA指出，AD在包括海马旁回在内的右下颞叶中显示出比对照更强的δ活性。3例AD用药后ADAS-J cog总分降低，而β-3频段（21.5-30 Hz）GFP增加。用药后与用药前相比，所有7个频段的GFP模式均与对照组相似。AD显示出比对照更高的Omega（全局复杂性）。广义频率（Phi）与MMSE、日本WAIS-R的全智商和操作智商得分相关。我们得到了4个微态类（A、B、C和D）。AD组和对照组在B和D类中存在地形差异。我们还发现，与对照组相比，AD中A类的贡献增加，C类的贡献减少。我们的GFP和LORETA结果表明，AD有脑功能障碍，特别是记忆障碍，多奈哌齐给他们的神经激活。Omega和Phi结果表明AD患者脑电场的空间复杂性增加，场变化的全局频率减慢与认知能力下降之间也存在密切关系。此外，微状态结构的差异反映了AD时脑组织的变化，持续时间的减少表明信息加工的基本构件缩短。

To clarify the neurophysiological characteristics of 17 mild Alzheimer's disease patients (ADs) (73.6±5.5 years) and 17 normal subjects (Controls) (70.3±8.9 years) using GFP, LORETA, Global components' and Microstate analyses. Stage 4 in FAST was defined as "mild" degree. We secondly investigated the brain electric changes before and 3 months after 5 mg donepezil hydrochloride administration in 3 ADs. Closed eyes resting EEG was recorded from 19 scalp sites (10/20 system).ADs showed higher GFP than Controls in delta band (1.5-6 Hz). LORETA specified that ADs showed stronger delta activity than Controls in right inferior temporal lobe including parahippocampal gyrus. Total ADAS-J cog scores decreased after the medication in 3 ADs, while beta-3 band (21.5-30 Hz) GFP increased. The GFP pattern in all of 7 frequency bands after the medication compared with before was similar to that of Controls compared with ADs. ADs showed higher Omega (global complexity) than the Controls. The Phi (generalized frequency) was correlated with the MMSE scores, the full and performance IQ scores of the Japanese WAIS-R. We obtained 4 microstate classes (A,B,C and D). There were topographic differences in class B and D between ADs and Controls. We also found increase of contribution of class A, and decrease of C in ADs compared to Controls. Duration of class C decreased in ADs.Our GFP and LORETA results suggest that ADs had brain dysfunctions, especially memory disturbances, and that donepezil gave them neural activation. Omega and Phi results indicate an increase in spatial complexity of the brain electric field in ADs, also a close relationship between slowing of the global frequency of field changes and the cognitive decline. Moreover, the differences of microstate configurations reflect cerebral organic changes in ADs, and the decrease of duration suggests a shortening of basic building block of information processing.