Special Seminar

Feb. 2 (Mon.), 2026
16:00-17:00 (JST)
at the Conference Room in the CiNet bldg.

Talk title: Neurochemical, behavioral, and cerebrospinal fluid dynamics during sleep for learning and memory in humans

Masako Tamaki
-RIKEN Hakubi Team Leader, Cognitive Somnology RIKEN Hakubi Research Team Cluster for Pioneering Research / Center for Brain Science
-Visiting Professor, Keio University School of Medicine

Host : Masahiko Haruno

Abstract:
Sleep is essential for the continuity and development of life. Sleep-related problems can alter brain function and cause potentially severe psychological and behavioral consequences. However, the role of sleep in the mind and behavior remains far from clear. In the first half of my talk, I will introduce our recent findings on cerebrospinal fluid (CSF) dynamics during sleep. While CSF dynamics during sleep have been implicated in the reduction of metabolic waste products in animals, how these processes are regulated in the human brain remains elusive. By developing a simultaneous sparse fMRI and polysomnography method, we demonstrate that spontaneous brain oscillations and neural events during sleep, such as slow waves and sleep spindles during deep NREM sleep as well as rapid eye movements and sawtooth waves during REM sleep, are tightly linked to frequent low-amplitude CSF fluctuations, contributing to faster CSF signal changes. In the second half of my talk, I will introduce our new study investigating how sleep facilitates learning and memory, leveraging a time-resolved simultaneous ultrahigh-field 7 Tesla magnetic resonance spectroscopy and polysomnography method. I will also cover my future research plans utilizing 7 Tesla MRI combined with other techniques to understand human sleep and cognition.