Department of Psychiatry, Osaka University Graduate School of Medicine, Osaka, Japan,
Department of Psychiatry, Nippon Life Hospital, Osaka, Japan,
Neuropsychobiology. 2019;77(4):206-218. doi: 10.1159/000495620. Epub 2019 Jan 17.
Dementia with Lewy bodies (DLB) is characterized by progressive cognitive decline, fluctuating cognition, visual hallucinations, rapid eye movement sleep behavior disorder, and parkinsonism. DLB is the second most common type of degenerative dementia of all dementia cases. However, DLB, particularly in the early stage, is underdiagnosed and sometimes misdiagnosed with other types of dementia. Thus, it is of great interest investigating neurophysiological markers of DLB.
We introduced exact low-resolution brain electromagnetic tomography (eLORETA)-independent component analysis (ICA) to assess activities of 5 electroencephalography (EEG) resting-state networks (RSNs) in 41 drug-free DLB patients.
Compared to 80 healthy controls, DLB patients had significantly decreased activities in occipital visual and sensorimotor networks, where DLB patients and healthy controls showed no age dependences in all EEG-RSN activities. Also, we found correlations between all EEG-RSN activities and DLB symptoms. Specifically, decreased occipital α activity showed correlations with worse brain functions related to attention/concentration, visuospatial discrimination, and global cognition. Enhanced visual perception network activity correlated with milder levels of depression and anxiety. Enhanced self-referential network activity correlated with milder levels of depression. Enhanced memory perception network activity correlated with better semantic memory, visuospatial discrimination function, and global cognitive function as well as with severer visual hallucination. In addition, decreased sensorimotor network activity correlated with a better semantic memory.
These results indicate that eLORETA-ICA can detect EEG-RSN activity alterations in DLB related to symptoms. Therefore, eLORETA-ICA with EEG data can be a useful noninvasive tool for sensitive detection of EEG-RSN activity changes characteristic of DLB and for understanding the neurophysiological mechanisms underlying this disease.
路易体痴呆（DLB）的特征是认知能力逐渐下降、认知波动、视幻觉、快速眼动睡眠行为障碍和帕金森病。DLB 是所有痴呆病例中第二常见的退行性痴呆类型。然而，DLB，特别是在早期，被诊断不足，有时被误诊为其他类型的痴呆。因此，研究 DLB 的神经生理标志物非常有趣。
我们引入了精确低分辨率脑电磁断层扫描（eLORETA）-独立成分分析（ICA）来评估 41 名未经药物治疗的 DLB 患者的 5 个脑电图（EEG）静息状态网络（RSN）的活动。
与 80 名健康对照相比，DLB 患者的枕叶视觉和感觉运动网络活动明显减少，而 DLB 患者和健康对照在所有 EEG-RSN 活动中均无年龄依赖性。此外，我们还发现了所有 EEG-RSN 活动与 DLB 症状之间的相关性。具体而言，枕部α活动减少与注意力/集中、视空间辨别和整体认知等大脑功能较差有关。视觉感知网络活动增强与抑郁和焦虑程度较轻相关。自我参照网络活动增强与抑郁程度较轻相关。记忆感知网络活动增强与语义记忆、视空间辨别功能和整体认知功能较好以及视觉幻觉较严重相关。此外，感觉运动网络活动减少与语义记忆较好有关。
这些结果表明，eLORETA-ICA 可以检测与症状相关的 DLB 中 EEG-RSN 活动的改变。因此，EEG 数据的 eLORETA-ICA 可以成为一种有用的非侵入性工具，用于敏感检测 DLB 特征性的 EEG-RSN 活动变化，并用于理解该疾病的神经生理机制。
