睡眠慢波是更深的非快速眼动睡眠的标志。通常假设灰质特性可以预测慢波密度,形态学,和健康成年人的光谱功率。这里,我们测试了27例中重度颅脑外伤患者的灰质体积(GMV)与慢波特征之间的关系(TBI;32.0±12.2岁,8名女性)与32名健康对照(29.2±11.5岁,九个女人)。参与者使用3特斯拉扫描仪进行了过夜多导睡眠图和脑MRI检查。进行全脑逐体素分析以比较组间的GMV。慢波密度,形态学,并计算频谱功率(0.4-6Hz),GMV是从丘脑中提取的,扣带回,脑岛,precuneus,和眶额叶皮层来测试慢波和灰质之间的关系,这些区域涉及慢波的产生和/或传播。与对照组相比,TBI患者的额叶和颞叶GMV显着降低,并且慢波频率略有降低。此外,眶额皮质GMV较高,脑岛,扣带皮质,和precuneus与较高的慢波频率和斜率有关,只有在健康的控制下。在健康参与者中,较高的眶额GMV也与较高的慢波密度相关。虽然我们观察到健康对照中GMV和慢波特征之间的预期关联,尽管GMV较低,但TBI组未观察到此类关联.这一发现挑战了GMV在慢波产生和形态中的假定作用。因为睡眠慢波在认知中起着关键作用,突触可塑性,和恢复性睡眠,在中度至重度创伤性脑损伤(TBI)后的脑萎缩中,了解它们与脑物质完整性的关系尤为重要。我们发现,参与慢波产生和传播的区域中较高的灰质体积(GMV)与健康个体中更快更陡的慢波有关。然而,在TBI参与者中未观察到这些关联,在灰质相对于对照组较低的患者中,GMV对慢波特性的贡献程度提出了质疑。这些发现挑战了我们目前对灰质完整性和慢波之间联系的理解,强调了这种关系的复杂性。
Sleep slow waves are the hallmark of deeper non-rapid eye movement sleep. It is generally assumed that gray matter properties predict slow-wave density, morphology, and spectral power in healthy adults. Here, we tested the association between gray matter volume (GMV) and slow-wave characteristics in 27 patients with moderate-to-severe traumatic brain injury (TBI, 32.0 ± 12.2 years old, eight women) and compared that with 32 healthy controls (29.2 ± 11.5 years old, nine women). Participants underwent overnight polysomnography and cerebral MRI with a 3 Tesla scanner. A whole-brain voxel-wise analysis was performed to compare GMV between groups. Slow-wave density, morphology, and spectral power (0.4-6 Hz) were computed, and GMV was extracted from the thalamus, cingulate, insula, precuneus, and orbitofrontal cortex to test the relationship between slow waves and gray matter in regions implicated in the generation and/or propagation of slow waves. Compared with controls, TBI patients had significantly lower frontal and temporal GMV and exhibited a subtle decrease in slow-wave frequency. Moreover, higher GMV in the orbitofrontal cortex, insula, cingulate cortex, and precuneus was associated with higher slow-wave frequency and slope, but only in healthy controls. Higher orbitofrontal GMV was also associated with higher slow-wave density in healthy participants. While we observed the expected associations between GMV and slow-wave characteristics in healthy controls, no such associations were observed in the TBI group despite lower GMV. This finding challenges the presumed role of GMV in slow-wave generation and morphology.