Sleep Flashcards
What are the four stages of sleep?
There are four stages of sleep: Non-REM (NREM) sleep (Stages 1, 2 & 3) and REM sleep (stage 4).
Stage 1 is the lightest stage of NREM sleep. Often defined by the presence of slow eye movements.
Stage 2 is the first actual stage of defined NREM sleep. Awakenings or arousals do not occur as easily as in Stage 1 sleep and the slow moving eye rolls discontinue.
Stage 3 is known as deep NREM sleep. The most restorative stage of sleep. Awakenings or arousals are rare and often it is difficult to awaken someone.
REM sleep known as the dreaming stage. Eye movements are rapid, moving from side to side and brain waves are more active than in Stages 2 & 3 of sleep.
When is optional sleep?
Optional sleep occurs in the following hours after core sleep and consists mainly of lighter (stage 1 and 2) sleep
When is REM sleep?
REM sleep occurs in stage 2
When is core sleep?
Core sleep occurs in the first 5 hours and consists mainly of deep (stage 3 and 4) sleep and half of the REM sleep
What is the bunker study?
Bunker study = showed we should have circadian rhythm of 25 hours. Subjects not given cues such as light or time which would encourage them to sleep. Revealed that each day the body delayed sleep by an extra hour.
How long do foetuses and babies sleeping in REM sleep?
New-born sleeps for 16 hours a day- spend half their sleeping time in REM sleep.
Foetus- spend all their time in REM sleep
REM sleep declines over time- older people become less active.
How to investigate sleep?
- subjective sleep quality
- movements during sleep
- EEG output
- dream content
What are the features of dreaming?
• not exclusive to REM, but REM dreams: -2x likely -6x longer and more vivid • unremembered consciousness or unconscious? • characteristics: • intensely visual (colour or B&W?) • no smell, taste, pain • contain movement • often bizarre/illogical • emotional (funny, frightening) • no awareness of dreaming
What is insomnia? What are the causes? What is the treatment?
Insomnia = delayed sleep onset, disturbed sleep, early morning waking. 1/3 have it.
Causes = psychological problems (depression, anxiety), other medical disorders (especially pain), social environment (alcohol, drugs) Treatment = hypnotic drugs, sleep education, sleep hygiene (behavioural changes), dealing with tension/intrusive thoughts (relaxation, cognitive approaches)
What is narcolepsy?
Narcolepsy (0.15% of the population) is daytime tiredness or suddenly falling asleep.
What is cataplexy?
Cataplexy is falling asleep/losing muscle control due to strong emotions such as laughter or anger.
What is sleep paralysis?
Sleep paralysis is the inability to speak or move when woken up. It is often caused by REM sleep intrusion into wakefulness. Increased prevalence in people who work shifts or suffer jet lag.
What is sleep latency?
Sleep latency = time to fall asleep
What is sleep deprivation?
Sleep deprivation mainly affects cortical (cortex) functions, the rest of the body is relatively unaffected. Upon sleep, only 1/3 of lost sleep is recovered and the priority is stage 4 and REM recovery.
What is Randy’s recovery sleep study?
• night 1 – extra 6.75 hrs • nights 2 & 3 – extra 4 & 2.5 hrs • regained 24% total lost sleep -7% stages 1 & 2 -68% stage 4 -53% REM
