What is core sleep?
First 5 hours
Most deep sleep (stages 3 and 4)
Half of Rapid Eye Movement (REM) sleep
When is optional sleep?
Next 2+ hours
Mostly stage 1&2
What did the Bunker study show?
that circadian rhythm (a roughly 24 hour cycle in the physiological processes of living beings) shifted to 25 hours
How does development affect sleep?
- reduction in total sleep time
- early reduction in %REM
- later reduction in stages 3&4: most lost by age 40
What is the mean sleep duration?
7.75 hours
Give 4 ways in which we can investigate sleep?
- subjective sleep quality
- movement during sleep
- EEG output
- dream content
Give features of REM dreams?
2x more likely
6x longer
more vivid
(even though dreams are not exclusive to REM)
What are the features of insomnia?
delayed sleep onset, disturbed sleep, early morning waking
Causes of insomnia?
psychological problems (depression, anxiety) other medical disorders e.g pain social environment (alcohol, drugs)
What is narcolepsy?
- occurs in 0.02-0.05% of population
- difficult to diagnose
- impaired quality of life
What are the features of narcolepsy?
- Sleep attacks - overwhelming sleepiness
- Cataplexy (paralysis of voluntary muscles)
- Vivid sleep-onset dreams/ hallucinations
What is sleep paralysis?
- conscious, eyes open, unable to move: hallucinations
- on going to sleep or on waking
- REM sleep intrustion
- 20-60% of people experience once in their life
How many nights sleep loss is there reserve capacity for?
1 night
