Vlad Vyazovskiy

@vyazovskiy.bsky.social

Sleep scientist

𝐀𝐩𝐩𝐥𝐢𝐜𝐚𝐭𝐢𝐨𝐧𝐬 𝐍𝐨𝐰 𝐎𝐩𝐞𝐧! ESRS is pleased to announce the launch of the ESRS-CSRS Exchange Programme - 10 ESRS early-career members will be selected to attend and present at the 18th Annual CSRS Conference, Zhengzhou, 28–30 August 2026. Full details and eligibility criteria here: lnkd.in/d-dQ-Wzf

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Preprint alert: If sleep is the cousin of death, torpor must be its fraternal twin. Yet, daily torpor is surprisingly dynamic when zooming in on the slow fluctuations in motility, brain activity, and temperature. Read (and see👀) more on bioRxiv! www.biorxiv.org/content/10.6...

Is torpor a quiescent state? Periodic motility and transient brain activation during daily torpor in Djungarian hamsters

Torpor is a hypometabolic state employed by many mammalian and non-mammalian species to cope with harsh environments. When exposed to a short photoperiod, Djungarian hamsters (Phodopus sungorus) enter daily torpor with body temperatures dropping as low as 15 degrees Celcius. Despite the widely-held notion that torpor is a form of deep sleep, torpid animals are not completely inactive but exhibit occasional movements reflected in an increase in EMG tone. Little is known about these EMG events during torpor and whether they have a functional role during the torpid state. We here analysed EEG, EMG, and brain temperature data from Djungarian hamsters, and used an automatic detection algorithm to identify periods of EMG activation during spontaneous daily torpor. The hamsters exhibited regular periods of motility that were invariably initiated during a decline in brain temperature and were followed by a brain temperature increase. The frequency of EMG events exhibited a negative correlation with brain temperature, such that lower brain temperature was associated with a higher frequency of EMG events. In addition, EMG events were associated with a pronounced increase in EEG power, especially between 9.5-15.5 Hz, which often started with an EEG pattern similar to an evoked potential preceding the increase in the EMG activity. On the contrary, micro-arousals during normothermic NREM sleep were associated with a decrease in EEG power, a decrease in brain temperature and were of shorter duration than torpor EMG events, indicating that the two phenomena may serve different purposes. We speculate that periodic motility associated with increased brain activity during torpor may play a role in thermoregulation, and help retain vigilance to potentially mitigate predation risk during this hypometabolic state. ### Competing Interest Statement The authors have declared no competing interest. Novo Nordisk Foundation, https://ror.org/04txyc737, NNF23OC0082427 Japan Agency for Medical Research and Development, JP21zf0127005 BBSRC, BB/X008711/1 MRC, MR/V013238/1 Wellcome Trust, https://ror.org/029chgv08, 227093/Z/23/Z Rhodes Trust, Rhodes Scholarship University of Oxford, https://ror.org/052gg0110, Clarendon Scholarship

biorxiv.org

🆕 𝗙𝗿𝗲𝘀𝗵 𝗼𝗳𝗳 𝘁𝗵𝗲 𝗣𝗿𝗲𝘀𝘀: A comprehensive analysis examining the phenomenological boundaries between #OutOfBodyExperience and #LucidDreams has been published in our research topic "𝘜𝘯𝘥𝘦𝘳𝘴𝘵𝘢𝘯𝘥𝘪𝘯𝘨 𝘊𝘰𝘯𝘴𝘤𝘪𝘰𝘶𝘴 𝘌𝘹𝘱𝘦𝘳𝘪𝘦𝘯𝘤𝘦 𝘥𝘶𝘳𝘪𝘯𝘨 𝘚𝘭𝘦𝘦𝘱". 🧠 #ConsciousnessResearch www.frontiersin.org/journals/psy...

Frontiers | Distinguishing out-of-body experiences from lucid dreaming: a phenomenological analysis

Despite extensive discussions, a consensus is lacking on whether out-of-body experiences (OBEs) and lucid dreams (LDs) should be considered as distinct categ...

frontiersin.org