Dmitry E. Postnov

Abstract: Over the last decade, important data have been obtained in the field of sleep physiology, new functions of astrocytes and pathways of interaction in the neuro-glia-vascular unit have been discovered, and the main patterns of the removal of harmful metabolites from the brain parenchyma have been identified. All together, this makes it possible to take a fresh look at the listed processes as a single global-local brain circuit that provides important functions for the organism as a whole. In particular, the phenomenon of local sleep, now proven by a number of experiments, requires a revision of the paradigm according to which sleep is a whole-brain state and thus opens the way to the concept of spatial-temporal dynamics of sleep. In turn, this raises the question of the presence and characteristics of a minimal “sleep unit” to which a group of neurovascular units corresponds. Further, this approach leads to the possibility of a local and time-unsynchronized process of cleaning the parenchyma from harmful metabolites. In my report, I provide an overview of specific data supporting the above assumptions and discuss a hypothesis that combines them into a consistent system. The work was supported by a grant from the Russian Science Foundation, #22-15-00143.

Speaker: Dmitry Postnov—chief researcher at the Department of Optics and Biophotonics, Saratov State University (SSU). In 1983, he graduated from the Department of Radiophysics at SSU, qualifying as an engineer. Over the next 17 years, he was engaged in research in the field of deterministic chaos and synchronization of non-periodic oscillations. Received a Candidate of Science degree in 1990 and a Doctor of Science degree in 2000. In 1997-1998. worked at Chungbuk University (South Korea), where he became interested in modeling processes in living systems. In subsequent years, he carried out a number of model and theoretical studies in the field of neuroscience, including neuro-glial ensembles, hemodynamics and filtration processes in the kidneys, vasomotor activity of vascular networks, etc. Since 2016, he has been focusing on mathematical modeling of processes in the brain parenchyma: cortical spreading depression, migraine waves, autoregulation of cerebral blood flow. Project leader for a number of grants from the RF Ministry of Education and Science and the Russian Science Foundation. In recent years, the focus has been on studying the relationships between the sleep-wake cycle, the activity of astrocytes and the process of removing harmful metabolites from the brain parenchyma.