Two nights of recovery sleep restores hippocampal connectivity but not episodic memory after total sleep deprivation

• Published in: Scientific reports Vol. 10; no. 1; p. 8774
• Main Authors: Chai, Ya, Fang, Zhuo, Yang, Fan Nils, Xu, Sihua, Deng, Yao, Raine, Andrew, Wang, Jieqiong, Yu, Meichen, Basner, Mathias, Goel, Namni, Kim, Junghoon J., Wolk, David A., Detre, John A., Dinges, David F., Rao, Hengyi
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 29.05.2020; Nature Publishing Group
• Subjects: 59/36; 631/378/2649; 631/477/2811; Adult; Brain mapping; Cognitive ability; Connectome; Female; Functional magnetic resonance imaging; Hippocampus; Hippocampus - diagnostic imaging; Hippocampus - physiopathology; Humanities and Social Sciences; Humans; Magnetic Resonance Imaging; Male; Memory; Memory, Episodic; Mental task performance; Middle Aged; multidisciplinary; Neural networks; Neuroimaging; Recovery of function; Science; Science (multidisciplinary); Sleep - physiology; Sleep deprivation; Sleep Deprivation - physiopathology; Young Adult
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-020-65086-x

Sleep deprivation significantly impairs a range of cognitive and brain function, particularly episodic memory and the underlying hippocampal function. However, it remains controversial whether one or two nights of recovery sleep following sleep deprivation fully restores brain and cognitive function. In this study, we used functional magnetic resonance imaging (fMRI) and examined the effects of two consecutive nights (20-hour time-in-bed) of recovery sleep on resting-state hippocampal connectivity and episodic memory deficits following one night of total sleep deprivation (TSD) in 39 healthy adults in a controlled in-laboratory protocol. TSD significantly reduced memory performance in a scene recognition task, impaired hippocampal connectivity to multiple prefrontal and default mode network regions, and disrupted the relationships between memory performance and hippocampal connectivity. Following TSD, two nights of recovery sleep restored hippocampal connectivity to baseline levels, but did not fully restore memory performance nor its associations with hippocampal connectivity. These findings suggest that more than two nights of recovery sleep are needed to fully restore memory function and hippocampal-memory associations after one night of total sleep loss.