Understanding how sleep affects the glymphatic system and human brain networks is crucial for elucidating the neurophysiological mechanism underpinning aging-related memory declines. We analyzed a multimodal dataset collected through magnetic resonance imaging (MRI) and polysomnographic recording from 72 older adults. A proxy of the glymphatic functioning was obtained from the Diffusion Tensor Image Analysis along the Perivascular Space (DTI-ALPS) index. Structural and functional brain networks were constructed based on MRI data, and coupling between the two networks (SC-FC coupling) was also calculated. Correlation analyses revealed that DTI-ALPS was negatively correlated with sleep quality measures [e.g., Pittsburgh Sleep Quality Index (PSQI) and apnea-hypopnea index]. Regarding human brain networks, DTI-ALPS was associated with the strength of both functional connectivity (FC) and structural connectivity (SC) involving regions such as the middle temporal gyrus and parahippocampal gyrus, as well as with the SC-FC coupling of rich-club connections. Furthermore, we found that DTI-ALPS positively mediated the association between sleep quality and rich-club SC-FC coupling. The rich-club SC-FC coupling further mediated the association between DTI-ALPS and memory function in good sleepers but not in poor sleepers. The results suggest a disrupted glymphatic-brain relationship in poor sleepers, which underlies memory decline. Our findings add important evidence that sleep quality affects cognitive health through the underlying neural relationships and the interplay between the glymphatic system and multimodal brain networks.

了解睡眠如何影响淋巴系统和人脑网络对于阐明支撑衰老相关记忆下降的神经生理机制至关重要。我们分析了通过磁共振成像 （MRI） 和多导睡眠图记录从 72 名老年人收集的多模态数据集。淋巴功能的代理是从沿血管间隙 （DTI-ALPS） 指数的弥散张量图像分析中获得的。基于 MRI 数据构建结构和功能脑网络，并计算两个网络之间的耦合 （SC-FC 耦合）。相关性分析显示，DTI-ALPS 与睡眠质量指标呈负相关 [例如，匹兹堡睡眠质量指数 （PSQI） 和呼吸暂停低通气指数]。关于人脑网络，DTI-ALPS 与涉及颞中回和海马旁回等区域的功能连接 （FC） 和结构连接 （SC） 的强度以及富俱乐部连接的 SC-FC 耦合有关。此外，我们发现 DTI-ALPS 正介导睡眠质量与 rich-club SC-FC 耦合之间的关联。Rich-Club SC-FC 耦合进一步介导了 DTI-ALPS 与良好睡眠者记忆功能之间的关联，但在睡眠不佳者中则没有。结果表明，睡眠不佳者的淋巴-大脑关系中断，这是记忆力下降的基础。我们的研究结果增加了重要证据，表明睡眠质量通过潜在的神经关系以及淋巴系统和多模态大脑网络之间的相互作用影响认知健康。