Why Can’t You Remember the Moment You Fall Asleep?

Why can’t you remember the exact moment you fall asleep? Every night, your brain gradually shifts from wakefulness into sleep, yet the final moments often disappear from memory. In this Ancient Human documentary, we explore the science of sleep onset, memory loss, brain activity, and consciousness. Discover what sleep experiments reveal about the moments before sleep, how ancient humans prepared their sleeping spaces 200,000 years ago, and what hunter-gatherer research tells us about the evolution of human sleep. Research & Sources: Wyatt et al. (1994) — Sleep onset is associated with retrograde and anterograde amnesia. Sleep. Hsiao et al. (2018) — The neurophysiological basis of the discrepancy between objective and subjective sleep during the sleep onset period. Sleep. Andrillon et al. (2024) — Sleepiness and the transition from wakefulness to sleep. Neurophysiologie Clinique. Mota et al. (2022) — Imagetic and affective measures of memory reverberation diverge at sleep onset in association with theta rhythm. NeuroImage. Wadley et al. (2020) — Fire and grass-bedding construction 200 thousand years ago at Border Cave, South Africa. Science. Yetish et al. (2015) — Natural Sleep and Its Seasonal Variations in Three Pre-industrial Societies. Current Biology. Samson et al. (2017) — Chronotype variation drives night-time sentinel-like behaviour in hunter–gatherers. Proceedings of the Royal Society B. #AncientHuman #SleepScience #HumanEvolution