Sleep, brain and behaviour laboratory
Sleep is traditionally defined and characterised by behavioural and electrophysiological criteria. For example, during sleep we are immobile and less responsive to the environment, and global cortical activity is distinctly different from an awake state. The differences between waking and sleep become less apparent as we look closer at the spatio-temporal patterns of cortical activity by recording local field potentials or neuronal spiking. It has been shown, that sleep-like patterns of neuronal activity are not uncommon during waking, even during active behaviours, and especially when the animals are drowsy or sleep-deprived. On the other hand, the main network oscillations during sleep – slow waves (~0.5-4 Hz) and spindles (~9-16 Hz) – are remarkably dynamic and idiosyncratic events, mostly occurring locally, and never encompassing the entire cortex at once. Slow waves are considered a reliable marker of preceding sleep-wake history, and a measure of sleep ‘intensity’. The ‘homeostatic principle’ postulates that the longer we stay awake, the more intense is our subsequent sleep. Recent evidence suggests that sleep homeostasis is a local process, and it has been identified both in cortical and subcortical structures, such as the dorsal striatum. Sleep spindles, which arise within the thalamocortical circuitry, also occur locally in the neocortex; and their occurrence varies greatly depending on the cortical region, the time of day and the immediate preceding state. Finally, individual cortical neurons are highly diverse with respect to the state dependency of their spiking activity, and, importantly, their response to preceding sleep-wake history. Over the last few decades our knowledge about sleep has progressed tremendously. However, the fundamental questions remain: what is ‘noise’ and what is ‘signal’ in cortical activity during sleep, and how does the global and precisely regulated state of sleep emerge from the activity (or lack thereof) of local and distributed, cortical and subcortical circuits.
In our research we use a broad range of techniques and approaches, such as behavioural tasks, electrophysiology, transgenic mouse models, local brain microstimulation and pharmacology.
Professor Vladyslav Vyazovskiy is a member of Oxford University's Sleep and Circadian Neuroscience Institute.
Video credit: Vicky Isley and Paul Smith (boredomresearch)
Video credit: University of Oxford Podcasts
Hear more from Prof Vyazovskiy on the Sleep Science Podcast Episode 4: Local sleep, circadian rhythms and torpor.
Collaborators
DPAG
Nuffield Department of Clinical Neurosciences
Department of Experimental Psychology
Department of Pharmacology
Department of Engineering Science
Radcliffe Department of Medicine
What's new
Vladyslav Vyazovskiy will head up new Gordon Research Conference
17 January 2024
Vladyslav Vyazovskiy will be the first chair of a new Gordon Research Conference on Neurobiology of Psychedelics.
Latest publications
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Defining an Ageing-Related Pathology, Disease or Syndrome: International Consensus Statement
Preprint
Short E. et al, (2024)
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Chronic insomnia, REM sleep instability and emotional dysregulation: A pathway to anxiety and depression?
Journal article
Riemann D. et al, (2024), J Sleep Res
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The future of JSR: Hybrid or Open Access publishing, and launch of a sister journal?
Journal article
Riemann D. et al, (2024), J Sleep Res
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Cortical evoked activity is modulated by the sleep state in a ferret model of tinnitus. A case study
Preprint
Milinski L. et al, (2024)