The Rhythms of sleep

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Objectives: The Student will

• Describe REM and NREM sleep• Create the 4 stages of the sleep cycle• Explain why we sleep• Trace the sleep disorders (cross reference the

graphic organizer)

Sleep story

• Eugene Aserinsky- 1952, studied son’s brain waves.

• Used EEG Measured Alpha waves, slow rhythm, high amplitude (height)

• 90 minutes- normal, then rapid eye movements, brain alert. But boy asleep.

• REM sleep- Rapid eye movements• Non-REM- Interim periods between

Compare and contrast

• NREM- Brief descriptions or none (sleep walking and talking happen here)

• REM- Vivid color, bizarre scenes

Delta waves compare and contrast

Realms of sleepStage 1. Feel self drifting on the edge of consciousness

Stage 2. Minor noises won’t disturb you

Stage 3. Breathing and pulse have slowed down

Stage 4. Deep sleep

REM. Increased eye movement, loss of muscle tone, dreaming

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Stages of sleep

• Stage 1- slower activity, fast brain. Close to awake. May remember fantasies, visuals

• Stage 2- Short bursts of fast electrical activity= Sleep spindles. Most noises won’t disturb

• Stage 3- deep sleep. Heart rate breathing slow down. Brain waves slow dramatically. Delta waves (slow waves, high peaks)

• Stage 4- Electrical activity increasing, talk and walk in this stage (unknown)

Typical night’s sleep for a young adult

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Your turnEarly in the evening, Joey’s parents find him walking around. They try to wake him, but he does not seem to respond. What kind of sleep is Joey in?1. REM sleep2. Fast-wave sleep (Stages 1 and 2)3. Slow-wave sleep (Stages 3 and 4)

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Your turnEarly in the evening, Joey’s parents find him walking around. They try to wake him, but he does not seem to respond. What kind of sleep is Joey in?1. REM sleep2. Fast-wave sleep (Stages 1 and 2)3. Slow-wave sleep (Stages 3 and 4)

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Why we sleepThe exact function of sleep is uncertain but sleep appears to provide time for the body to carry out important functions.To eliminate waste products from musclesTo repair cellsTo strengthen the immune systemTo recover abilities lost during the day

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Why we sleep

• Dream to forget- Mental trash• Repair cells, muscles, • strengthen immune system• Memory

Mental consequences of sleeplessness

• Chronic sleep deprivation causes release of cortisol (stress hormone) damage learning and memory

• 2/3 of Americans don’t get 8 hrs• American students- 6 hrs

Student sleep cycle

Sleep disordersSleep deprivation leads to decreases in physical and mental functioning.Sleep apneaBreathing briefly stops during sleep, causing the person to choke and gasp and momentarily waken.

NarcolepsySudden and unpredictable daytime attacks of sleepiness or lapses into REM sleep

Staying up late and not allowing oneself enough sleep2/3 of Americans get fewer than recommended 8 hours

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Other consequences

• Sleep apnea- disorder in which breathing stops during sleep causing the person to choke and gasp

• Causes: blocking of air passages, failure of brain to control respiration

• Narcolepsy- sudden and unpredictable daytime attacks of sleepiness or actual sleep

• Causes: degeneration of neurons in hypothalamus, most likely genetic

Narcolepsy

Insomnia

• The most common sleep disorder• Can’t get to sleep or stay up all night• Treated with reduction of caffeine, exercise at

appropriate times of day= not right before sleep

• Use sleeping pills with caution

Mental benefits

• Good sleep promotes benefits• Sleep =memory consolidation • Process by which synaptic charges associated

with memory become durable and stable• German study 3 groups- math problem• Group with best sleep= best results

Summary

• Sleep cycle waves • REM• Disorders/Benefits (Evidence)