RETRACTED: Test-retest reliability of coupling between cerebrospinal fluid flow and global brain activity after normal sleep and sleep deprivation
Weiwei Zhao, Joy Rao, Ruosi Wang, Ya Chai, Tianxin Mao, Peng Quan, Yao Deng, Wenwen Chen, Shilei Wang, Bowen Guo, Qingyun Zhang, Hengyi Rao
Abstract
• The reliability of the gBOLD-CSF coupling index is robust in participants with normal sleep but diminishes after total sleep deprivation. • The reliability of gBOLD-CSF coupling varies across brain networks, with lower-order networks (visual, somatomotor, and attention) exhibiting higher ICC values than higher-order networks (default-mode, limbic, and frontoparietal), but this pattern is less pronounced after sleep deprivation. • The gBOLD-CSF coupling index is a promising method for assessing glymphatic clearance, with sleep history being an important consideration in studies of glymphatic system changes or longitudinal research. The glymphatic system (GS) plays a key role in maintaining brain homeostasis by clearing metabolic waste during sleep, with the coupling between global blood-oxygen-level-dependent (gBOLD) and cerebrospinal fluid (CSF) signals serving as a potential marker for glymphatic clearance function. However, the test-retest reliability and spatial heterogeneity of gBOLD-CSF coupling after different sleep conditions remain unclear. In this study, we assessed the test-retest reliability of gBOLD-CSF coupling following either normal sleep or total sleep deprivation (TSD) in 64 healthy adults under controlled laboratory conditions. The reliability was high after normal sleep (ICC = 0.763) but decreased following TSD (ICC = 0.581). Moreover, spatial heterogeneity was evident in participants with normal sleep, with lower-order networks (visual, somatomotor, and attention) showing higher ICC values compared to higher-order networks (default-mode, limbic, and frontoparietal). This spatial variation was less distinct in the TSD group. These results demonstrate the robustness of the gBOLD-CSF coupling method and emphasize the significance of considering sleep history in glymphatic function research.