Rosales-Lagarde Alejandra, Rodriguez-Torres Erika E, Itzá-Ortiz Benjamín A, Miramontes Pedro, Vázquez-Tagle Génesis, Enciso-Alva Julio C, García-Muñoz Valeria, Cubero-Rego Lourdes, Pineda-Sánchez José E, Martínez-Alcalá Claudia I, Lopez-Noguerola Jose S
Consejo Nacional de Ciencia y Tecnología, Mexico City, Mexico.
Área Académica de Gerontología, San Agustín Tlaxiaca, Mexico.
Front Psychol. 2018 Jul 17;9:1205. doi: 10.3389/fpsyg.2018.01205. eCollection 2018.
In Older Adults (OAs), Electroencephalogram (EEG) slowing in frontal lobes and a diminished muscle atonia during Rapid Eye Movement sleep (REM) have each been effective tracers of Mild Cognitive Impairment (MCI), but this relationship remains to be explored by non-linear analysis. Likewise, data provided by EEG, EMG (Electromyogram) and EOG (Electrooculogram)-the three required sleep indicators-during the transition from REM to Non-REM (NREM) sleep have not been related jointly to MCI. Therefore, the main aim of the study was to explore, with results for Detrended Fluctuation Analysis (DFA) and multichannel DFA (mDFA), the Color of Noise (CN) at the NREM to REM transition in OAs with MCI vs. subjects with good performances. The comparisons for the transition from NREM to REM were made for each group at each cerebral area, taking bilateral derivations to evaluate interhemispheric coupling and anteroposterior and posterior networks. In addition, stationarity analysis was carried out to explore if the three markers distinguished between the groups. Neuropsi and the Mini-Mental State Examination (MMSE) were administered, as well as other geriatric tests. One night polysomnography was applied to 6 OAs with MCI (68.1 ± 3) and to 7 subjects without it (CTRL) (64.5 ± 9), and pre-REM and REM epochs were analyzed for each subject. Lower scores for attention, memory and executive funcions and a greater index of arousals during sleep were found for the MCI group. Results confirmed that EOGs constituted significant markers of MCI, increasing the CN for the MCI group in REM sleep. The CN of the EEG from the pre-REM to REM was higher for the MCI group vs. the opposite for the CTRL group at frontotemporal areas. Frontopolar interhemispheric scaling values also followed this trend as well as right anteroposterior networks. EMG Hurst values for both groups were lower than those for EEG and EOG. Stationarity analyses showed differences between stages in frontal areas and right and left EOGs for both groups. These results may demonstrate the breakdown of fractality of areas especially involved in executive functioning and the way weak stationarity analyses may help to distinguish between sleep stages in OAs.
在老年人（OA）中，额叶脑电图（EEG）减慢以及快速眼动睡眠（REM）期间肌肉张力缺失减弱均已成为轻度认知障碍（MCI）的有效追踪指标，但这种关系仍有待通过非线性分析进行探究。同样，脑电图（EEG）、肌电图（EMG）和眼电图（EOG）（这三项是所需的睡眠指标）在从REM睡眠向非快速眼动（NREM）睡眠过渡期间提供的数据尚未与MCI进行联合关联分析。因此，本研究的主要目的是利用去趋势波动分析（DFA）和多通道DFA（mDFA）的结果，探究患有MCI的老年人与表现良好的受试者在从NREM睡眠向REM睡眠过渡时的噪声颜色（CN）情况。对每组在每个脑区从NREM睡眠向REM睡眠的过渡情况进行比较，采用双侧导联来评估半球间耦合以及前后网络和后网络。此外，进行平稳性分析以探究这三个指标是否能区分不同组。对受试者进行了神经心理测试和简易精神状态检查表（MMSE）评估，以及其他老年病测试。对6名患有MCI的老年人（68.1±3岁）和7名无MCI的受试者（对照组）（64.5±9岁）进行了一晚的多导睡眠监测，并对每个受试者的REM睡眠前和REM睡眠阶段进行了分析。MCI组在注意力、记忆力和执行功能方面得分较低，且睡眠期间觉醒指数较高。结果证实，EOG构成了MCI的重要指标，在REM睡眠中MCI组的CN增加。在额颞叶区域，MCI组从REM睡眠前到REM睡眠的EEG的CN高于对照组，反之亦然。额极半球间标度值以及右侧前后网络也呈现这种趋势。两组的EMG赫斯特值均低于EEG和EOG。平稳性分析显示，两组在额叶区域以及左右EOG的不同阶段存在差异。这些结果可能表明，特别是涉及执行功能的区域的分形性遭到破坏，以及弱平稳性分析有助于区分老年人睡眠阶段的方式。
