Department of Electrical Engineering, College of Engineering and Petroleum, Kuwait University, Kuwait City, Kuwait 13060
Department of Electrical and Computer Engineering, University of California at San Diego, La Jolla, CA 92093.
eNeuro. 2021 Nov 19;8(6). doi: 10.1523/ENEURO.0194-21.2021. Print 2021 Nov-Dec.
Studies in animals have demonstrated a strong relationship between cortical and hippocampal activity, and autonomic tone. However, the extent, distribution, and nature of this relationship have not been investigated with intracranial recordings in humans during sleep. Cortical and hippocampal population neuronal firing was estimated from high γ band activity (HG) from 70 to 110 Hz in local field potentials (LFPs) recorded from 15 subjects (nine females) during nonrapid eye movement (NREM) sleep. Autonomic tone was estimated from heart rate variability (HRV). HG and HRV were significantly correlated in the hippocampus and multiple cortical sites in NREM stages N1-N3. The average correlation between HG and HRV could be positive or negative across patients given anatomic location and sleep stage and was most profound in lateral temporal lobe in N3, suggestive of greater cortical activity associated with sympathetic tone. Patient-wide correlation was related to δ band activity (1-4 Hz), which is known to be correlated with high γ activity during sleep. The percentage of statistically correlated channels was weaker in N1 and N2 as compared with N3, and was strongest in regions that have previously been associated with autonomic processes, such as anterior hippocampus and insula. The anatomic distribution of HRV-HG correlations during sleep did not reproduce those usually observed with positron emission tomography (PET) or functional magnetic resonance imaging (fMRI) during waking. This study aims to characterize the relationship between autonomic tone and neuronal firing rate during sleep and further studies are needed to investigate finer temporal resolutions, denser coverages, and different frequency bands in both waking and sleep.
动物研究表明，皮质和海马体活动与自主神经张力之间存在很强的关系。然而，在人类睡眠期间，尚未通过颅内记录来研究这种关系的程度、分布和性质。皮质和海马体群体神经元的放电活动是从局部场电位（LFPs）的高γ频段活动（HG）中估算出来的，该频段活动的频率范围在 70 到 110 赫兹之间，记录自 15 名受试者（9 名女性）的非快速眼动（NREM）睡眠期间。自主神经张力是从心率变异性（HRV）中估算出来的。在 NREM 阶段 N1-N3 中，海马体和多个皮质部位的 HG 和 HRV 显著相关。考虑到解剖位置和睡眠阶段，HG 和 HRV 之间的平均相关性在患者之间可能是正相关或负相关，并且在 N3 中外侧颞叶最为明显，提示与交感神经张力相关的皮质活动更大。患者范围的相关性与 δ 频段活动（1-4 赫兹）有关，已知该频段活动在睡眠期间与高 γ 活动相关。与 N3 相比，N1 和 N2 的统计相关通道百分比较弱，而在先前与自主过程相关的区域（如前海马体和岛叶）最强。睡眠期间 HRV-HG 相关性的解剖分布与清醒期间通常与正电子发射断层扫描（PET）或功能磁共振成像（fMRI）相关的那些分布不同。本研究旨在描述睡眠期间自主神经张力与神经元放电率之间的关系，需要进一步研究以研究清醒和睡眠期间更精细的时间分辨率、更密集的覆盖范围和不同的频段。
