【摘要】 目的探讨轻度认知功能障碍(MCI)患者在工作记忆时脑电图相干性变化,验证MCI存在皮质联络障碍的假说。方法对13例MCI患者(MCI组)和13例年龄、性别和文化程度相互匹配的健康体检者(正常对照组)进行脑电图检查,包括安静状态和3种难度逐次增加的工作记忆状态(WM)。计算各状态额叶、中央、顶叶、颞叶和枕叶位点半球间相干系数及各状态左、右额-中央、中央-顶、顶-枕、颞-中央、颞-顶各半球内相干系数并进行比较。结果MCI组在安静状态及工作记忆状态各频段半球间及半球内相干值比对照组高。WM1状态下各位点半球间及半球内相干值均显著小于安静状态及WM2、WM3状态。在任一频段,MCI组及对照组额-中央,中央-顶,顶-枕的相干值显著高于颞-中央及颞-顶的相干值。结论MCI患者在工作记忆状态时存在代偿机制;MCI患者颞叶与其他脑区域之间存在联系障碍,并且这种障碍在正常衰老过程中已经出现。更多还原

【Abstract】 Objective To observe alterations of memory-related EEG interhemispheric and intrehemispheric coherence in patients with mild cognitive impairment(MCI). Methods EEGs were recorded at rest and during working memory task with three levels of working memory load in 13 patients with MCI and 13 controls. Interhemispheric EEG coherence for 5 homologous electrode pairs of right and left frontal, central, parietal, temporal and occipital was computed at rest and during working memory task. EEG intrehemispheric coherence at four conditions was measured for 10 electrode pairs of left and right fronto-central, centro-parietal, parieto-occipital, temporo-central and temporo-parietal. Results Compared with the normal controls, the MCI patients had higher coherences in both the intra- and interhemispheric at resting EEG or during working memory task. Both the intra- and interhemispheric coherences during WM1 task were significantly lower than those during other three conditions. In every frequency band, the temporo-central, temporo-parietal coherence was significantly decreased compared with fronto-central, centro-parietal, parieto-occipital coherence. Conclusion The results suggested that MCI may be associated with compensatory processes. The results support the hypothesis that there was a breakdown of the functional link between temporal with other cortical sites in the MCI patients, and the deficits of cortical connections are involved in normal elderly control.更多还原