Neurophysiology + medicine of sleep: REM/NREM stages, two-process model, orexin/narcolepsy, slow-wave activity, synaptic homeostasis hypothesis, sleep-replay-memory, polysomnography, circadian-sleep coupling, insomnia.
Sleep Biology
REM/NREM stage architecture
Aserinsky-Kleitman 1953 REM discovery; Rechtschaffen-Kales 1968 → AASM 2007 staging: NREM (N1/N2/N3 deep slow-wave) + REM cycle ~90 min…
Borbély two-process sleep model
Borbély 1982: sleep regulated by interaction of homeostatic process S (sleep-pressure builds with wake, dissipates with sleep — adenosine +…
Orexin / narcolepsy (Mignot)
Mignot 1999: canine-narcolepsy → hypocretin-2 receptor mutation; Lin-Mignot 1999 hypocretin/orexin neuropeptide. Type-1 narcolepsy (with…
Synaptic homeostasis hypothesis (Tononi-Cirelli SHY)
Tononi-Cirelli 2003/2014 SHY: wakefulness drives net potentiation of cortical synapses; sleep (esp. slow-wave) restores baseline via global…
Memory replay during sleep (Wilson-McNaughton)
Wilson-McNaughton 1994: hippocampal place-cell sequences from awake exploration replay during slow-wave-sleep at compressed (~20×)…
Polysomnography sleep staging
PSG = simultaneous EEG (multi-channel) + EOG (eye movements) + EMG (chin/leg) + ECG + respiration + SpO2 across one night. Gold standard…
Circadian-sleep coupling (SCN)
Suprachiasmatic nucleus (SCN) ~20k neurons in anterior hypothalamus drive circadian alerting / sleep-propensity rhythm via projections to…
Insomnia & CBT-I (cognitive-behavioural therapy for insomnia)
Edinger-Carney 2008 CBT-I: stimulus-control + sleep-restriction + cognitive-restructuring + sleep-hygiene + relaxation. Effect-size d~1.0;…
Sleep deprivation cognitive impairment
Van Dongen-Dinges 2003: 6 hours/night × 14 days produces cognitive deficits equivalent to 1 night of total sleep deprivation, but…
REM-behaviour-disorder (RBD) prodrome
Schenck 1986 RBD: loss of REM-atonia → patient enacts dreams (kicking / punching). iRBD = isolated/idiopathic RBD without overt…
Glymphatic CSF clearance during sleep (Nedergaard)
Xie-Nedergaard 2013: cerebrospinal-fluid bulk-flow through perivascular spaces (glymphatic system) clears metabolic waste (Aβ, tau) ~60%…
Sleep-immune coupling (Cohen-Prather)
Cohen 2009 / Prather 2015: sleep duration / quality predicts vaccine-response, common-cold susceptibility, all-cause mortality. …
REM (Aserinsky-Kleitman 1953)
Aserinsky-Kleitman 1953 REM-sleep discovery; modern Saper 2010 sleep-circuit + GABA-VLPO + monoaminergic.
Two-process (Borbely 1982)
A Borbely 1982 two-process: process-S homeostatic + process-C circadian; modern review Borbely 2016.
Circadian (Konopka-Benzer 1971)
Konopka-Benzer 1971 period-mutant Drosophila; modern Hall-Rosbash-Young Nobel 2017 PER/TIM/CRY/CLOCK molecular clock.
Sleep + memory (Stickgold-Walker 2005)
Stickgold-Walker 2005 sleep-dependent memory consolidation; modern reactivation + replay + offline-processing.
Glymphatic (Iliff-Nedergaard 2012)
Iliff-Nedergaard 2012 glymphatic-system; modern AQP4 polarization + sleep-driven CSF flow + amyloid clearance.
Orexin/narcolepsy (de Lecea 1998)
de Lecea 1998 + Sakurai 1998 orexin/hypocretin; modern selective-orexin-receptor-antagonist suvorexant 2014 insomnia drug.