REM sleep
Vivid dreaming stage
REM sleep is the phase of sleep characterized by rapid eye movements, vivid dreaming, and near-complete muscle paralysis.
It cycles throughout the night, with periods lengthening toward morning.
REM stands for "rapid eye movement." The brain is highly active during REM sleep, which appears essential for memory consolidation and emotional processing: I woke up in the middle of REM sleep and remembered every detail of my dream.
Lack of muscle tone
- paralysisLoss of muscle function
- muscle relaxationSoftening of contracted fibers
- heart rate variabilityBeat-to-beat timing differences
- irregular breathingAbnormal respiratory rhythm
twitching · body temperature · blood pressure · pupil dilation · metabolic rate
Unusually intense sleep imagery
- nightmareFrightening dream causing wakefulness
- subconsciousBelow conscious awareness
- imageryVivid descriptive language
- surrealDreamlike and strange
symbolism · hallucination · storyline · emotional processing · recall · bizarre · fantastical · oneiric
Neurological excessive drowsiness condition
- cataplexyEmotion-induced muscle paralysis
- insomniaPersistent inability to rest
- parasomniaAbnormal behavior while sleeping
- sleepwalkingAmbulatory behavior during slumber
Built-in sleep-wake cycle
- NREMSleep lacking eye movement
- reboundReturn after deflection
- fragmentationBreaking into smaller pieces
- durationLength of existence
frequency · distribution · cycling · periodicity · morning hours
Electrical signals from neurons
- EEGNeural activity recording
- electroencephalogramBrain wave recording
- neuronsSignal-transmitting brain cells
- cortexOrgan's external tissue
hippocampus · amygdala · thalamus · acetylcholine · serotonin · norepinephrine · synaptic · plasticity
Gaining knowledge gradually
- emotional regulationManaging internal feeling states
- creativityCapacity for original thought
- problem-solvingAddressing challenges methodically
- mood regulationControlling emotional states
atonia
Lack of muscle tone
- paralysisLoss of muscle function
- muscle relaxationSoftening of contracted fibers
- heart rate variabilityBeat-to-beat timing differences
irregular breathing · twitching · body temperature · blood pressure · pupil dilation · metabolic rate
vivid dreams
Unusually intense sleep imagery
- nightmareFrightening dream causing wakefulness
- subconsciousBelow conscious awareness
- imageryVivid descriptive language
surreal · symbolism · hallucination · storyline · emotional processing · recall · bizarre · fantastical · oneiric · imagination
narcolepsy
Neurological excessive drowsiness condition
- cataplexyEmotion-induced muscle paralysis
- insomniaPersistent inability to rest
- parasomniaAbnormal behavior while sleeping
circadian rhythm
Built-in sleep-wake cycle
- NREMSleep lacking eye movement
- reboundReturn after deflection
- fragmentationBreaking into smaller pieces
duration · frequency · distribution · cycling · periodicity · morning hours
brainwaves
Electrical signals from neurons
- EEGNeural activity recording
- electroencephalogramBrain wave recording
- neuronsSignal-transmitting brain cells
cortex · hippocampus · amygdala · thalamus · acetylcholine · serotonin · norepinephrine · synaptic · plasticity · neurotransmitters
learning
Gaining knowledge gradually
- emotional regulationManaging internal feeling states
- creativityCapacity for original thought
- problem-solvingAddressing challenges methodically
- sleepnap, doze, slumber, naps, snooze
- dreamsnightmare, daydream, nightmares, dreams, lucid dream
- mental statesknowledge, conscious, mood, anxious, memory
- natural cyclescircadian rhythm, seasons, tides, water cycle, lunar cycle
- restresting, napping, dozing, slumber, slumbering
- dreamlanddream world, dreamscape, lucid dream, daydream, sweet dreams
REM sleepdeep sleep
Unconsciousness hard to rouse
non-REM sleep · dreamless sleep · light sleep · restorative sleep
REM sleepwakefulness
State of being conscious
alertness · waking state · arousal · vigilance · coma
sleep, sleepy, movement, dreaming, sleeping, sleeper, sleepiness, REM, REM cycles