HPC · Science Deep Dive 18 June 2026 · revised 16 October 2026

REM Sleep: What the Evidence Shows About Memory, Mood and Health.

REM sleep is a busy, chemically distinct state of the brain, and it builds toward morning. Lab studies link it to emotional memory and to one kind of creative problem solving. Cohort studies, mostly of older adults, link less REM to higher death rates and, in one study, to dementia; both links still need to be confirmed. Here is what the science actually says, and what to do with it.

Section: Bio · Sleep
Reading time: 22 min read
Sources: 36 · reviewed

01What REM Sleep Is

REM sleep builds toward morning, so an early alarm can cut into it

REM sleep is the stage of sleep in which your eyes move quickly beneath closed lids. Those rapid eye movements gave the stage its name when researchers first recorded them in sleepers.^[1] During REM your muscles go slack while your brain stays busy. REM is defined by this state of the brain; dreaming happens in it.

What does REM do? Studies link it to several jobs. The first is storing emotional memory, memories with feeling attached, for the long term.^[4]^[15] The second is a reset of background brain activity, seen as changes in a brainwave (EEG) proxy for how excitable the brain is.^[23] The third is linking recent experience with older knowledge.^[6] In one small nap experiment, naps that included REM were linked to better solving of word puzzles that people had been primed for.^[6]

REM is not spread evenly across the night. It usually first appears about ninety minutes after you fall asleep and takes up a larger share of sleep later in the night.^[12] Its total amount varies with age and with how long you sleep.^[35] So an early alarm may remove sleep from a REM-rich part of the night.^[12]

The history

In NREM sleep, the deeper, slower stages that fill most of the first half of the night, the brain does work that looks restorative. One hypothesis holds that NREM scales back connections between brain cells.^[13] In mice, sleep in general was also linked to greater clearance of waste from the brain than wakefulness.^[14] REM works differently. It lifts brain activity to near-waking levels.^[12] At the same time, it holds back norepinephrine, a chemical that would normally make that brain activity feel like stress.^[5]^[12]

That chemistry is at the centre of one model of how REM handles emotional memory. The model proposes that emotional memories are reactivated during REM and may become less distressing while their content is kept.^[5] On this model, low norepinephrine lets that happen without setting off the body's stress response.^[5] The work involves the amygdala, an area that tags threat and emotion.^[5] It also involves the prefrontal cortex, the planning area at the front of the brain.^[5] The model's authors called this "overnight therapy".^[5]

REM-like sleep is not unique to mammals. Birds have it, and one lizard, the Australian bearded dragon, shows REM-like brain activity.^[36] The lizard finding suggests this kind of sleep may be at least three hundred million years old.^[36] That may date it to the shared ancestor of reptiles, birds and mammals.^[36] The lizard finding also challenges an older view, which holds that similar sleep states evolved separately in mammals and birds.^[36] Which view is right is still open.

This article covers what the brain does during REM, how strong each finding is, what cuts REM short and what you can do tonight. Its case is that REM is a distinct working state of the brain. It is worth protecting, not spare time at the end of the night. REM has its own neurochemical signature, a mix of brain chemicals unlike waking or deep sleep, and its own brain rhythms. The evidence ranges from electrodes placed in patients' brains and imaging in animals to long-running studies of mostly older adults and small controlled experiments.

That matters because common habits may cut REM without people noticing. Alcohol near bedtime can delay and reduce REM.^[31]^[32] In one experiment in healthy men whose sleep was deliberately scheduled later than usual, regular caffeine delayed the start of REM without significantly changing total REM.^[33] An early alarm may cut into a REM-rich part of the night.^[12] Knowing how REM works shows what each habit may cost.

02The Mechanism

The Chemical Shift That Sets REM Sleep Apart

The switch that starts REM sleep sits deep in the brainstem, in a small cluster of cells called the sublaterodorsal nucleus (SLD). When these cells fire, they set off the chain of events that defines REM.^[17]^[20] Nearby brainstem cells step up their release of acetylcholine, a chemical messenger linked to attention in waking hours.^[3]^[16] At the same time, two brainstem centres that keep you alert fall almost silent.^[12] One, the locus coeruleus, releases norepinephrine; the other, the dorsal raphe, releases serotonin.^[12]

The result is a brain that is busy but chemically changed. The outer brain becomes active. Theta oscillations, a slow brain rhythm of four to eight waves a second, sweep through the hippocampus, a memory hub, and the prefrontal cortex. They are thought to help coordinate the replay and mixing of recent experience.^[4]^[19] Bursts of activity called PGO waves travel from the brainstem to the visual areas at the back of the brain.^[19] In animal studies, PGO waves are associated with theta rhythms.^[19] Their contribution to human dreaming and memory remains proposed.^[19] Signals from the brainstem also switch off the muscles. This temporary paralysis, called muscle atonia, stops the body from acting out dreams.^[17]

One chemical runs low in this busy brain. Norepinephrine, which normally rises when the brain is this active, falls to its lowest level of the whole day and night.^[5] One model treats this low point as a proposed condition for processing emotional memory.^[5]

That matters because the brain in REM is not simply switched on. It works in a mode with no waking match, like a machine that runs at full power with its alarm system turned down.

The REM chemical cascade: the brainstem switch (SLD) turns on cells that release acetylcholine and quiets the cells that release norepinephrine and serotonin. Theta rhythms are thought to help coordinate memory replay between the hippocampus and the outer brain, and one model proposes that the amygdala reprocesses emotional memories while norepinephrine is at its lowest. That model treats the low point as a proposed condition for emotional-memory processing.

Diagram · HPC

Studies link REM to several jobs. The first is emotional memory consolidation, the storing of emotional memories. One model, called "sleep to forget, sleep to remember", proposes that emotional memories are reactivated during REM and may become less distressing while their content is retained.^[5] On this model, with norepinephrine at its lowest, these memories replay without the stress response that came with them the first time.^[5] Researchers call this fading of the emotional response depotentiation.

Sleep also strengthens emotional memories more than neutral ones, so the process is selective.^[15]

The second job is associative recombination, linking ideas in new ways. During REM, parts of the prefrontal cortex quiet down, which loosens the filter that keeps waking thought on track.^[11] One account proposes that sleep helps integrate recently acquired information with past knowledge.^[10]

The third job is neural recalibration, a reset of background brain activity. One study, with brain recordings in people and cell imaging in rodents, found that REM sleep lowers aperiodic neural activity across the outer brain.^[23] In people this is a brainwave (EEG) proxy for how excitable the brain is, not a direct measure of brain cells.^[23] The idea is that a day of learning strengthens connections and makes brain signals noisier, and REM resets this. In that study, REM-related changes in this EEG proxy predicted overnight word-pair memory retention; the link is a correlation.^[23]

REM may also help the brain forget. In mice, cells in the hypothalamus that make melanin-concentrating hormone (MCH) were active mainly during REM sleep. Switching these cells on increased forgetting of memories that depend on the hippocampus.^[18] Switching them off with light reduced that forgetting.^[18] If the same holds in people, REM would edit memory as well as store it, keeping some memories and clearing others.

Remembering and forgetting in the same brain state would solve a problem. A brain that only stored emotional experiences, with no way to prune them, would build an ever-growing archive. The mouse work points to one way the pruning could happen. In mice, at least, REM sleep acts less like a tape recorder than like an editor.^[18]

REM builds toward morning, taking a larger share of sleep later in the night.^[12] That pattern follows a daily timing signal, sometimes called a circadian gate, that sets when REM is most likely. The pull toward REM usually peaks toward the end of your usual night, in step with the body's daily temperature rhythm.^[33]

So waking at six rather than half past seven, for example, may remove sleep from a REM-rich part of the night.^[12]

REM is only one part of the night. NREM and REM may work in sequence. In rats, learned activity patterns in the prefrontal cortex reappear during slow-wave sleep alongside short hippocampal bursts called sharp-wave ripples; this may support memory consolidation.^[7] One account proposes that NREM and REM make complementary contributions to memory.^[10] One theory, the synaptic homeostasis hypothesis, holds that NREM scales back connections across the brain.^[13] Its authors discuss the possibility that REM helps stabilise selected connections, among other possible roles.^[13]

In mice, natural sleep or anaesthesia was linked to greater clearance of waste proteins, including amyloid-β, than wakefulness.^[14] The clearance runs through the glymphatic system, a fluid-based cleaning network in the brain.^[14] This experiment did not establish a REM-specific benefit. The two stages may do different jobs. NREM may do more of the brain's physical upkeep, and REM more of the work on memory and emotion. That division is a proposal, not a tested result.

03Evidence

The Five Strongest Studies on REM Sleep and Human Function

01The claim

The single load-bearing finding

The hero study finds EEG tracked retention.

A lab experiment that separates REM from other sleep answers a different question from a cohort study. A cohort study follows a group of people for years and may track their REM against death rates. The experiment can test cause; the cohort can only show a link. The ranking below scores five studies on design, sample, measurement, strength of causal evidence and replication.^[9] It marks down studies that cannot rule out reverse causation, such as early illness lowering REM, and notes where a result rests on a single study.

Key study result

EEG tracked retention

02How we measured

Grading the REM sleep trials

Studies scored on design, sample, rigour, causality, replication, citations.

For REM sleep science, the central methodological challenge is separating causation from reverse causation, because REM loss may be a symptom of the same conditions, such as early neurodegeneration, that the epidemiological studies are trying to predict.

Rubric weights

Design/30

Sample/20

Rigour/15

Causality/15

Replication/10

Citations/10

03The spread

Heterogeneity across 5 studies

Methodological quality across the ranked studies.

The lab studies are tight but small. Each measured a specific brain signal under controlled conditions, and each link between a REM signal and memory or emotion is a correlation.^[23]^[8]^[4] The disease studies are a different kind of evidence. The dementia association comes from a small observational cohort and does not establish cause.^[21] The death-rate link appeared in two cohorts.^[22] These cohorts were mostly white Americans, and early brain disease may lower REM rather than the reverse.^[21]

Rubric spread

→ 67 /100

Highest to lowest rubric score across the ranked studies.

04Beyond the top five

Wider evidence

What the wider evidence adds.

The creativity evidence sits in the middle. One nap study in this selection compared people whose naps included REM, nappers without REM and quiet rest; it controlled for time away from the task.^[6] The REM group's gain on primed word puzzles was statistically significant. But the gain depended on prior priming, and new, unprimed puzzles did not improve.^[6] The creativity finding is limited to a small primed word-puzzle experiment.^[6] Whether REM gives a general creativity boost is not known.

The studies

5 studies, ranked.

Below: the anchor study in full; then every study's rubric score; then the supporting studies in ranked order.

01Anchor

Human REM sleep recalibrates neural activity in support of memory formation

Lendner, Niethard & Mander 2023 Multi-Modal · Cross-Species · Intracranial EEG

REM sleep lowered an EEG proxy for how excitable the brain is. In healthy adults, changes in this proxy predicted overnight word-pair retention; the link is a correlation, not a test of cause.

It is the only study in this set to pair recordings inside the human brain with imaging in rodents. Scalp recordings came from 40 healthy adults and recordings inside the brain from 15 patients with epilepsy. It measures a brain signal, not just behaviour, though in people that signal is a proxy for excitability.

Rubric breakdown

Design26/30

Sample13/20

Rigour14/15

Causality13/15

Replication8/10

Citations8/10

Total 82/100

The strongest studies, ranked by methodological weight.

Each scored 0 to 100 against a six-criterion rubric, tagged by design and year; the anchor leads. No study in this set reaches the rubric-90 tier.

Anchor (Rank 1) Supporting

Rank Authors & title Journal · Year Finding Score

van der Helm, Yao & Dutt

REM sleep depotentiates amygdala activity to previous emotional experiences

2011

In 34 healthy young adults (18 sleep, 16 wake), a night of sleep, compared with the same length of time awake during the day, significantly reduced the amygdala's response to previously viewed emotional images on a brain scan (fMRI). Lower prefrontal REM gamma, a fast brain rhythm, was associated with the larger overnight drop, a correlation. The link between the amygdala and the middle of the prefrontal cortex also grew stronger. This overnight drop is the depotentiation, or fading of the emotional response, that the title names.

77/100

Pase, Himali & Grima

Sleep architecture and the risk of incident dementia in the community

2017

In 321 adults over sixty, each one-percentage-point lower REM share was associated with about 9% higher dementia risk over a mean of twelve years; 32 people developed dementia. People who developed dementia averaged 17% REM, against 20% in those who did not. No other sleep stage showed a significant link.

72/100

Nishida, Pearsall & Buckner

REM sleep, prefrontal theta, and the consolidation of human emotional memory

2009

In 31 young adults, 15 were assigned a nap and 16 stayed awake. The nap benefit concerned negative emotional pictures. REM correlations were based on the 13 nappers who reached REM. In them, how well people kept emotional memories, but not neutral ones, was correlated with how much REM sleep they got. It was correlated most closely with prefrontal theta power, the strength of the theta rhythm over the front of the brain during REM. The link was strongest on the right side. This points to a possible brain-rhythm marker for emotional memory, not a shown cause.

70/100

Cai, Mednick & Harrison

REM, not incubation, improves creativity by priming associative networks

2009

People who reached REM sleep during a nap scored about 40% higher than their own morning score on primed items. The task was the Remote Associates Test, a word puzzle that asks for the word linking three others. Primed items were puzzles whose parts they had seen earlier in the day. People who napped without REM, or rested quietly, showed no significant gain, and new, unprimed puzzles did not improve. The study compared people whose naps included REM, nappers without REM and quiet rest; it controlled for time away from the task. People were randomly assigned to a nap or to quiet rest, and nap groups were then formed by whether the nap reached REM. In the primary experiment, the REM nap group had ten people, the nap group without REM had six and the quiet-rest group had nine.

67/100

04Stakes

Four areas of health linked to short REM sleep

Some effects of losing REM show up within days in lab studies. Others are links that appear over years in cohort studies, and they may not be causes.

01 System 01

Cognitive & Neurodegeneration

In a community cohort of 321 adults over sixty, each one-percentage-point lower REM share was associated with about 9% higher dementia risk over a mean of twelve years; 32 people developed dementia.^[21] The association comes from a small observational cohort and does not establish cause: early brain disease may lower REM, rather than REM loss causing dementia.^[21] Separately, some people act out their dreams because of REM sleep behaviour disorder. In the isolated form, the disorder has no other known cause.^[28] People with it have a high long-term risk of a synucleinopathy, a group of related brain diseases.^[28] These include Parkinson's disease, dementia with Lewy bodies and multiple system atrophy.^[28] That high risk makes the disorder a strong early warning sign of these diseases, separate from simply getting little REM.^[28]

02 System 02

Emotional Dysregulation

One review proposes that unstable REM sleep may be an early cause of mood disorders.^[27] Its authors note that the idea rests on theory and on cross-sectional studies, which measure people at a single point in time, not on trials.^[27] Sleep disturbance and nightmares are common in post-traumatic stress disorder (PTSD), while studies of REM abnormalities have produced mixed results.^[25] One proposal is that repeated nightmares may reflect a failure of the overnight fading of emotion.^[26] One model proposes that too little REM leaves the amygdala's emotional charge in place, which may raise reactivity the next day.^[24]

System 03

Cardiovascular & Metabolic

Each five-percentage-point lower REM share was associated with a 13% higher death rate from any cause in a cohort of older men; another cohort including middle-aged men and women found a similar association.^[22] The older-men cohort followed over 2,600 men for about twelve years.^[22] Whether low REM causes this, or marks underlying frailty, is not known. Sleep loss in general impairs blood sugar control, lowers leptin, a hormone that signals fullness, and raises ghrelin, which signals hunger.^[30]

04 System 04

Immune Function

In healthy male volunteers, selective REM deprivation lowered levels of IgA antibody, a part of the immune system. Levels had still not returned to baseline after three nights of recovery sleep.^[29]

05Protocol

Four Sleep Habits That May Help Protect REM

These are sleep habits the article suggests, informed by the studies rather than tested as rules. Because REM builds toward morning, several of them aim to leave the end of the night in place.

The protocol, as a sequence.

Fixed → Evening → Afternoon → Morning

01 Step 01 · Fixed

Anchor Total Duration

Allow enough sleep time that you do not routinely cut off the later part of your night. Keep a regular sleep window.

Why

REM usually first appears about ninety minutes after sleep onset and builds toward morning.^[12] Its total amount varies with age and sleep duration.^[35]

Common mistake

Letting bedtime and waking time drift from day to day. Try to keep sleep timing regular.

02 Step 02 · Evening

Eliminate Alcohol Before Bed

Avoid using alcohol as a sleep aid: it can delay and reduce REM. Keeping drinks away from bedtime is a suggestion, not a tested cut-off.

Why

In a pooled analysis of studies in healthy adults, each additional gram of alcohol per kilogram of body weight was linked to about thirty minutes more delay to the first REM period, compared with a control condition.^[32] Total REM fell by about forty minutes per additional gram per kilogram.^[32] Even low doses delayed the first REM period.^[31]

Common mistake

Using a nightcap to fall asleep faster. A nightcap can delay the first REM period and reduce total REM, even if it helps you fall asleep.

03 Step 03 · Afternoon

Manage Caffeine and Temperature

Keep caffeine away from the hours before bed, as general advice rather than a tested cut-off. Keep the bedroom at a comfortable temperature for sleep.

Why

In twenty healthy men whose sleep was deliberately scheduled later than usual, regular caffeine delayed the start of REM without significantly changing total REM.^[33] A review describes room temperatures of about 19 to 21°C, with bedding, as comfortable for sleep.^[34]

Common mistake

"I fall asleep fine after evening coffee." Falling asleep easily does not tell you how caffeine affected your REM.

04 Step 04 · Morning

Protect the Final Hours

Wake naturally when you can. If you need an alarm, leave enough time for a full night instead of trying to time it to exact multiples of ninety minutes.

Why

Because REM builds toward morning, an early alarm may cut into a REM-rich part of the night.^[12] This is an inference from sleep patterns, not the result of an alarm trial.

Common mistake

Hitting snooze again and again. Repeated alarms can interrupt sleep.

Operational logic

Most of the habits target something linked to later or less REM: a short night, alcohol, caffeine or an early alarm. The temperature advice is about comfort. No study here compared the habits with each other, so they are not ranked.

The evidence behind the habits varies. For alcohol, a pooled analysis found that higher doses were linked to more delay and less REM.^[32] However, the analysis could not establish whether the time between drinking and bed made a difference.^[32] For caffeine, the evidence is one experiment in healthy men on a delayed sleep schedule.^[33] For temperature, a review describes a comfortable room range but gives no tested threshold for REM.^[34] The alarm habit follows from how REM is spread across the night, not from a trial of alarms.^[12]

06Verdict

The verdict.

"REM is a state of the brain first. Dreaming is what happens inside it." Editorial synthesis

Bottom line

REM is defined by the brain state, not the dream, and it builds toward morning.

The argument

Science now knows far more about REM sleep than the fact that people dream in it. During REM, norepinephrine falls to its lowest level. One study found that REM-related changes in a brainwave proxy for excitability predicted overnight word-pair memory retention, a correlation. A separate model proposes that REM helps process emotional memory. A small nap study found that people whose naps included REM improved on primed word puzzles. Cohort studies link less REM to higher death rates and, in one small community cohort of older adults, to dementia. Whether low REM causes either is not known. Because REM builds toward morning, an early alarm can cut into a later REM period.

Sleep is not one uniform block that you either got enough of or did not. Sleep architecture, the pattern of stages across the night, changes as the night goes on: REM takes a larger share of sleep later in the night.^[12] One account proposes that NREM and REM make complementary contributions to memory.^[10] So losing the end of a night can cut into a later REM period.^[12]

The people studied matter. The older-men death-rate cohort and the dementia cohort were older populations; the second death-rate cohort also included middle-aged men and women.^[22]^[21] The older-men cohort was all men, and over 90% of them were white.^[22] These mostly white US samples limit how far the links generalise, especially to more racially diverse populations. The lab evidence comes from other groups of people and from animals. It has its own limits, such as small samples. How large the long-term health effects are is still an open question.

The protocol's four habits are all things you can change, and none is a tested rule. Leave enough time for sleep, and avoid using alcohol as a sleep aid. Keep caffeine away from the hours before bed and the bedroom at a comfortable temperature. Wake naturally when you can, rather than cutting the night short with an alarm. Treat REM as the evidence describes it: a distinct working state of the brain, not spare time at the end of the night.

No comparison figure runs here. The prose above does not resolve to one clean effect size to set against another, and this magazine does not manufacture a number to fill the space. The verdict stands on the evidence as written.

01Claim

REM is a distinct processing state

REM sleep has its own chemistry: acetylcholine high, norepinephrine at its lowest and theta rhythms active. One study linked REM-related changes in a brainwave proxy for excitability to overnight word-pair retention, a correlation. Links to emotional memory and to new links between ideas rest on smaller studies and proposed models.

02Consequence

The long-term costs of short REM are uncertain

The long-term consequences of low REM remain uncertain. Cohort studies link a low share of REM to higher death rates and, in one small community cohort of older adults, to dementia.

03Lever

Protect the final hours

The habits named in the protocol are things you can change, not fixed conditions. None was tested as a rule, and no study here ranks them.

Put it to work

Where this science goes next on HPC

AssessmentChronotype AssessmentScore where you actually stand Protocol90-Day Sleep Optimisation ProtocolTurn the mechanism into practice GlossaryREM SleepThe definition, held to the evidence

07Bibliography

The bibliography.

36 sources · ~5h est. corpus read · 36 visible

Meta · 2 Review · 7 Journal · 27

Type

Sort

01 Journal

Aserinsky, E., & Kleitman, N1953

Regularly occurring periods of eye motility, and concomitant phenomena, during sleep

Science273–274

doi: 10.1126/science.118.3062.273
a b
02 Journal

Dement, W., & Kleitman, N1957

The relation of eye movements during sleep to dream activity: An objective method for the study of dreaming

Journal of Experimental Psychology339–346

doi: 10.1037/h0048189
↩
03 Journal

Hobson, J. A., & McCarley, R. W1977

The brain as a dream state generator: An activation-synthesis hypothesis of the dream process

American Journal of Psychiatry134(12) · 1335-1348

doi: 10.1176/ajp.134.12.1335
↩
04 Journal

Nishida, M., Pearsall, J., Buckner, R. L., & Walker, M. P2009

REM sleep, prefrontal theta, and the consolidation of human emotional memory

Cerebral Cortex1158–1166

doi: 10.1093/cercor/bhn155
a b c
05 Journal

Walker, M. P., & van der Helm, E2009

Overnight therapy? The role of sleep in emotional brain processing

Psychological Bulletin731–748

doi: 10.1037/a0016570
a b c d e f g h i j
06 Journal

Cai, D. J., Mednick, S. A., Harrison, E. M., Kanady, J. C., & Mednick, S. C2009

REM, not incubation, improves creativity by priming associative networks

Proceedings of the National Academy of Sciences106(25) · 10130-10134

doi: 10.1073/pnas.0900271106
a b c d e
07 Journal

Peyrache, A., Khamassi, M., Benchenane, K., Wiener, S. I., & Battaglia, F. P2009

Replay of rule-learning related neural patterns in the prefrontal cortex during sleep

Nature Neuroscience919–926

doi: 10.1038/nn.2337
↩
08 Journal

van der Helm, E., Yao, J., Dutt, S., Rao, V., Saletin, J. M., & Walker, M. P2011

REM sleep depotentiates amygdala activity to previous emotional experiences

Current Biology2029–2032

doi: 10.1016/j.cub.2011.10.052
↩
09 Journal

Stickgold, R2005

Sleep-dependent memory consolidation

Nature1272–1278

doi: 10.1038/nature04286
↩
10 Review

Walker, M. P., & Stickgold, R2006

Sleep, memory, and plasticity

Annual Review of Psychology139–166

doi: 10.1146/annurev.psych.56.091103.070307
a b c
11 Journal

Muzur, A., Pace-Schott, E. F., & Hobson, J. A2002

The prefrontal cortex in sleep

Trends in Cognitive Sciences475–481

doi: 10.1016/S1364-6613(02)01992-7
↩
12 Review

Brown, R. E., Basheer, R., McKenna, J. T., Strecker, R. E., & McCarley, R. W2012

Control of sleep and wakefulness

Physiological Reviews1087–1187

doi: 10.1152/physrev.00032.2011
a b c d e f g h i j k l m n
13 Journal

Tononi, G., & Cirelli, C2014

Sleep and the price of plasticity: From synaptic and cellular homeostasis to memory consolidation and integration

Neuron12–34

doi: 10.1016/j.neuron.2013.12.025
a b c
14 Journal

Xie, L., Kang, H., Xu, Q., et al2013

Sleep drives metabolite clearance from the adult brain

Science373–377

doi: 10.1126/science.1241224
a b c
15 Journal

Payne, J. D., & Kensinger, E. A2010

Sleep's role in the consolidation of emotional episodic memories

Current Directions in Psychological Science290–295

doi: 10.1177/0963721410383978
a b
16 Journal

Fraigne, J. J., Torontali, Z. A., Snow, M. B., & Peever, J. H.2015

REM sleep at its core - circuits, neurotransmitters, and pathophysiology

Frontiers in Neurology6 · 123

doi: 10.3389/fneur.2015.00123
↩
17 Journal

Peever, J., & Fuller, P. M2017

The biology of REM sleep

Current Biology

doi: 10.1016/j.cub.2017.10.026
a b
18 Journal

Izawa, S., Chowdhury, S., Miyazaki, T., et al2019

REM sleep-active MCH neurons are involved in forgetting hippocampus-dependent memories

Science1308–1313

doi: 10.1126/science.aax9238
a b c
19 Review

Gao, J.-X., Yan, G., Li, X.-X., Xie, J.-F., Spruyt, K., Shao, Y.-F., & Hou, Y.-P.2023

The ponto-geniculo-occipital (PGO) waves in dreaming: An overview

Brain Sciences13(9) · 1350

doi: 10.3390/brainsci13091350
a b c d
20 Journal

Luppi, P. H., Malcey, J., Chancel, A., Duval, B., Cabrera, S., & Fort, P.2025

Neuronal network controlling REM sleep

Journal of Sleep Research34(2) · e14266

doi: 10.1111/jsr.14266
↩
21 Journal

Pase, M. P., Himali, J. J., Grima, N. A., et al2017

Sleep architecture and the risk of incident dementia in the community

Neurology1244–1250

doi: 10.1212/WNL.0000000000004373
a b c d e
22 Journal

Leary, E. B., Watson, K. T., Ancoli-Israel, S., et al2020

Association of rapid eye movement sleep with mortality in middle-aged and older adults

JAMA Neurology1241–1251

doi: 10.1001/jamaneurol.2020.2108
a b c d e
23 Journal

Rubric 82/100

Lendner, J. D., Niethard, N., Mander, B. A., van Schalkwijk, F. J., Schuh-Hofer, S., Schmidt, H., Knight, R. T., Born, J., Walker, M. P., Lin, J. J., & Helfrich, R. F2023

Human REM sleep recalibrates neural activity in support of memory formation

Science Advances

doi: 10.1126/sciadv.adj1895
a b c d e
24 Review

Goldstein, A. N., & Walker, M. P2014

The role of sleep in emotional brain function

Annual Review of Clinical Psychology679–708

doi: 10.1146/annurev-clinpsy-032813-153716
↩
25 Journal

Germain, A2013

Sleep disturbances as the hallmark of PTSD: Where are we now?

American Journal of Psychiatry372–382

doi: 10.1176/appi.ajp.2012.12040432
↩
26 Review

Levin, R., & Nielsen, T. A2007

Disturbed dreaming, posttraumatic stress disorder, and affect distress: A review and neurocognitive model

Psychological Bulletin482–528

doi: 10.1037/0033-2909.133.3.482
↩
27 Journal

Riemann, D., Dressle, R. J., Benz, F., Spiegelhalder, K., Johann, A. F., Nissen, C., Hertenstein, E., Baglioni, C., Palagini, L., Krone, L., Perlis, M. L., Domschke, K., Berger, M., & Feige, B.2025

Chronic insomnia, REM sleep instability and emotional dysregulation: A pathway to anxiety and depression?

Journal of Sleep Research34(2) · e14252

doi: 10.1111/jsr.14252
a b
28 Review

Hogl, B., Stefani, A., & Videnovic, A2018

Idiopathic REM sleep behaviour disorder and neurodegeneration, an update

Nature Reviews Neurology40–55

doi: 10.1038/nrneurol.2017.157
a b c d
29 Journal

Ruiz, F. S., Andersen, M. L., Martins, R. C., et al2012

Immune alterations after selective rapid eye movement or total sleep deprivation in healthy male volunteers

Innate Immunity44–54

doi: 10.1177/1753425910385962
↩
30 Review

Knutson, K. L., Spiegel, K., Penev, P., & Van Cauter, E2007

The metabolic consequences of sleep deprivation

Sleep Medicine Reviews163–178

doi: 10.1016/j.smrv.2007.01.002
↩
31 Journal

Ebrahim, I. O., Shapiro, C. M., Williams, A. J., & Fenwick, P. B2013

Alcohol and sleep I: Effects on normal sleep

Alcoholism: Clinical and Experimental Research539–549

doi: 10.1111/acer.12006
a b
32 Meta

Gardiner, C., Weakley, J., Burke, L. M., Roach, G. D., Sargent, C., Maniar, N., Huynh, M., Miller, D. J., Townshend, A., & Halson, S. L.2025

The effect of alcohol on subsequent sleep in healthy adults: A systematic review and meta-analysis

Sleep Medicine Reviews80 · 102030

doi: 10.1016/j.smrv.2024.102030
a b c d e
33 Journal

Weibel, J., Lin, Y. S., Landolt, H. P., et al2021

Regular caffeine intake delays REM sleep promotion and attenuates sleep quality in healthy men

Journal of Biological Rhythms384–394

doi: 10.1177/07487304211013995
a b c d
34 Journal

Harding, E. C., Franks, N. P., & Wisden, W.2019

The temperature dependence of sleep

Frontiers in Neuroscience13 · 336

doi: 10.3389/fnins.2019.00336
a b
35 Meta

Ohayon, M. M., Carskadon, M. A., Guilleminault, C., & Vitiello, M. V2004

Meta-analysis of quantitative sleep parameters from childhood to old age in healthy individuals: Developing normative sleep values across the human lifespan

Sleep1255–1273

doi: 10.1093/sleep/27.7.1255
a b
36 Journal

Shein-Idelson, M., Ondracek, J. M., Liaw, H. P., Reiter, S., & Laurent, G2016

Slow waves, sharp waves, ripples, and REM in sleeping dragons

Science590–595

doi: 10.1126/science.aaf3621
a b c d

The protocol card