Beijing Dementia Key Lab, Dementia Care and Research Center, Peking University Institute of Mental Health (Sixth Hospital), Beijing 100191, China.
NHC Key Laboratory of Mental Health, National Clinical Research Center for Mental Disorders, Peking University, Sixth Hospital, Beijing 100191, China.
Cereb Cortex. 2023 Nov 27;33(23):11279-11286. doi: 10.1093/cercor/bhad365.
Electroencephalography can assess connectivity between brain hemispheres, potentially influencing cognitive functions. Much of the existing electroencephalography research primarily focuses on undirected connectivity, leaving uncertainties about directed connectivity alterations between left-right brain hemispheres or frontal-posterior lobes in mild cognitive impairment. We analyzed resting-state electroencephalography data from 34 mild cognitive impairment individuals and 23 normal controls using directed transfer function and graph theory for directed network analysis. Concerning the dominance within left-right hemispheres or frontal-posterior lobes, the mild cognitive impairment group exhibited decreased connectivity within the frontal compared with posterior brain regions in the delta and theta bands. Regarding the dominance between the brain hemispheres or lobes, the mild cognitive impairment group showed reduced connectivity from the posterior to the frontal regions versus the reverse direction in the same bands. Among all participants, the intra-lobe frontal-posterior dominance correlated positively with executive function in the delta and alpha bands. Inter-lobe dominance between frontal and posterior regions also positively correlated with executive function, attention, and language in the delta band. Additionally, interhemispheric dominance between the left and right hemispheres positively correlated with attention in delta and theta bands. These findings suggest altered cerebral dominance in mild cognitive impairment, potentially serving as electrophysiological markers for neurocognitive disorders.
脑电图可以评估大脑半球之间的连通性，从而可能影响认知功能。现有的脑电图研究大多集中在非定向连通性上，对于轻度认知障碍患者左右大脑半球或额-顶叶之间的定向连通性变化仍存在不确定性。我们使用定向转移函数和图论对 34 名轻度认知障碍患者和 23 名正常对照者的静息态脑电图数据进行了分析，用于定向网络分析。关于左右半球或额-顶叶之间的优势，与后脑区域相比，轻度认知障碍组在 delta 和 theta 波段中，前脑区域的连通性降低。关于大脑半球或脑叶之间的优势，与反向方向相比，轻度认知障碍组在前脑区域到后脑区域的连通性降低。在所有参与者中，同波段内额叶-顶叶优势与 delta 和 alpha 波段的执行功能呈正相关。额叶和后叶之间的脑叶间优势与 delta 波段的执行功能、注意力和语言也呈正相关。此外，左-右半球间的半球间优势与 delta 和 theta 波段的注意力呈正相关。这些发现表明轻度认知障碍中存在大脑优势改变，可能作为神经认知障碍的电生理标志物。
