Sleep Flashcards
Is sleep structured?
Yes
What is the basic architecture of sleep?
stage 1 stage 2 stage 3 - deep sleep stage 4 - deep sleep (sleep staircase) REM sleep dispersed in between
What stages of sleep are deep sleep? how do we know?
Stages 3 and 4
slow brain waves
What is REM sleep?
Rapid eye movement sleep
brain actively inhibits voluntary muscles - only movement is flickering of eyelids. literally paralysed.
What is core sleep? What is optional sleep?
core:
first 5 hours
most of deep sleep (stage 3 & 4)
half of REM sleep
optional:
next 2+ hours
mostly stage 2&1
What happens to sleep when all time/light cues are removed? Bunker study
Circadian rhythm is 25 hours - each phase of sleep is shifted by an hour
How many hours will newborns sleep for?
16 hours
At what age have most changes in sleep occurred?
Around 10
What are 3 key developmental changes in sleep as we age?
reduction in total sleep time
early reduction in % REM
later reduction in stages 3&4 (deep sleep) - most lost by age 40 - also, reduction in parasomnias (sleepwalking, sleeptalking, night terrors).
What is the mean sleep duration?
7.75 hours
Give 3 ways to investigate sleep
subjective sleep quality
movement during sleep
EEG output
dream content
What is sleep latency?
Time it takes to onset of sleep
What are 2 features of REM dreams?
2x more likely
6x longer and more vivid
What % of the population has insomnia?
30%
What are the features of insomnia?
Delayed sleep onset Disturbed sleep Early morning waking Wake up a lot during the night - feel like they've been awake longer than they've been asleep not much stage 3/4/REM
What are some possible causes of insomnia?
Psychological problems (depression, anxiety) Medical disorders (esp. pain) Social environment (alcohol, drugs)
What are 3 approaches to treat insomnia?
hypnotic drugs
sleep education
sleep hygiene - behavioural changes
dealing with tension/intrusive thoughts - relaxation and cognitive approaches
What is narcolepsy?
Sleep attacks
Cataplexy (paralysis of voluntary muscles)
Vivid sleep-onset dreams (hallucinations?)
What % of the population suffers from narcolepsy?
0.02-0.05%
What is sleep paralysis?
On going to sleep or on waking, you are conscious with eyes open but unable to move, hallucinations
REM sleep intrusion
Which people are more likely to experience sleep paralysis?
shift workers
those with jet lag
Who did a study of 264 hours (11 days) without sleep?
… it’s his name not his occupation
Randy Gardner
What were found to be the main health issues after 11 days without sleep?
dry eyes
swollen lymph nodes
transient heart murmur (disappeared a month later)
fall in skin temp and core body temp (metabolic shut down)
problems with speech, memory
minor hand tremor
NO decline in balance and walking –> core brain functions remained intact, only cortical functions were affected
How much of his lost sleep did Randy regain after 11 days without sleep? What stage was the majority of this?
24% (around 1/3)
Stage 4 and REM
What body functions will mainly be affected by sleep deprivation?
Cortical functions (memory, speech etc)
