Inducing Sleep Spindles with Auditory Closed-Loop Stimulation

Since the early days of human spaceflight astronauts have reported and complained about sleep deficiency and fatigue during missions [1]. These sleep disturbances might be in part due to environmental factors such as noise, temperature and light intensity interfering with astronauts’ sleep maintenance. It is well established knowledge that sleep loss is associated with poor health and performance decrements, both of which are crucial for space missions [2,3]. Therefore we investigate a potential countermeasure for astronauts’ sleep disturbances.

Auditory stimulation during sleep is proposed as a method to enhance sleep stability by inducing sleep spindles. Sleep spindles are well studied electrical oscillations in the brain that occur during sleep. Previous studies [4,5,6] have provided some evidence that these brain oscillations have a sleep-protective function. Together with the Memory and Sleep group of Prof. Dr. Lucia Talamini at the University of Amsterdam we develop ways to induce sleep spindles to further "decouple" the brain from external stimuli and improve sleep quality for future space missions. Such a countermeasure would not only make space travel safer but potentially alleviate common sleep issues around the globe.

References

1. Barger, L. K., Flynn-Evans, E. E., & Czeisler, C. A. (2014). Prevalence of Sleep Deficiency and Hypnotic Use Among Astronauts Before, During and After Spaceflight: An Observational Study. Lancet Neurol., 102(9), 1207–1211. https://doi.org/10.1016/S1474-4422(14)70122-X
2. Flynn-Evans, E., Gregory, K., Arsintescu, L., Whitmire, A., & Leveton, L. B. (2015). Evidence report: Risk of performance decrements and adverse health outcomes resulting from sleep loss, circadian desynchronization, and work overload in human health and performance risks of space exploration missions NASA human research roadmap. Retrieved from https://humanresearchroadmap.nasa.gov/evidence/reports/sleep.pdf
3. Van Dongen, H. P. A., Maislin, G., Mullington, J. M., & Dinges, D. F. (2003). The cumulative cost of additional wakefulness: dose-response effects on neurobehavioral functions and sleep physiology from chronic sleep restriction and total sleep deprivation. Sleep, 26(2), 117–26. https://academic.oup.com/sleep/article/26/2/117/2709164
4. Dang-Vu, T. T., McKinney, S. M., Buxton, O. M., Solet, J. M., & Ellenbogen, J. M. (2010). Spontaneous brain rhythms predict sleep stability in the face of noise. Current Biology, 20(15). https://doi.org/10.1016/j.cub.2010.06.032
5. Kim, A., Latchoumane, C., Lee, S., Kim, G. B., Cheong, E., Augustine, G. J., & Shin, H.-S. (2012). Optogenetically induced sleep spindle rhythms alter sleep architectures in mice. Proceedings of the National Academy of Sciences, 109(50), 20673–20678. https://doi.org/10.1073/pnas.1217897109
6. Wimmer, R. D., Astori, S., Bond, C., Rovo, Z., Chatton, J.-Y., Adelman, J. P., Franken, P., Luthi, A. (2012). Sustaining sleep spindles through enhanced SK2 channel activity consolidates sleep and elevates arousal threshold. https://doi.org/10.1523/JNEUROSCI.2313-12.2012