// SLEEP

Sleep

Circadian regulation, melatonin, sleep architecture, brain restoration

Sleep isn't rest — it's active restoration. During deep N3 sleep, your glymphatic system flushes beta-amyloid and tau proteins from the brain. Your pineal gland releases melatonin in response to darkness, regulated by the suprachiasmatic nucleus (SCN). Disrupted sleep architecture is now linked to Alzheimer's, metabolic syndrome, and immune dysfunction.

SLEEP ARCHITECTUREOne night \u00B7 ~8 hoursWAKEREMMemory consolidationN1Light · Theta wavesN2Sleep spindles · 45-55%N3Deep · Glymphatic peak11PM12AM1AM2AM3AM4AM5AM6AM7AMCycle 1Cycle 2Cycle 3Cycle 4Cycle 5Growth hormone pulseGlymphatic clearance \u219160% \u00B7 Xie et al., 2013Melatonin onset (DLMO) ~9PMCore temp \u2193 1-2\u00B0FGlymphatic system clears 60% more waste during deep sleep \u00B7 Xie et al., Science 2013

Mechanism

Light \u2192 RetinaipRGCsSCN Master ClockPineal: Melatonin \u2191Core temp \u2193VLPO: Sleep switchN1 \u2192 N2 \u2192 N3 \u2192 REM \u00D7 4-6 cyclesN3: Glymphatic clearance \u00B7 \u03B2-amyloid removalXie et al., Science 2013
60%

increase in glymphatic clearance during deep sleep — your brain's waste removal system activates primarily in N3 sleep

Xie et al., Science 2013

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