https://www.dailymail.com/sciencetech/article-15796087/sleep-deprivation-brain-damage-alzheimers.html
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The review found that the time when someone is asleep is when the brain actively strengthens and stores memories made during the day.
Without enough sleep, the hippocampus quickly begins to work poorly, leading to weaker connections between brain cells and harmful waste to build up.
Even one night of poor or missed sleep could start the downward spiral, causing weaker memory replay and higher levels of toxic proteins known as beta-amyloid and tau..."