Sleep Flashcards
Endo and Exo research?
Siffre Aschoff & Weber Czeisler Decoursey's chipmunks and weasels Morgan's mutant hamsters Stephens melatonin/light = breast cancer
Infradian rhythms research?
Empson (males have monthly cycles)
Jet Lag research?
Recht et al baseballers - e-w=44% , w-e=37%
Shift lag research?
Chernobyl
3 mile island disaster
Martine et al - link between shift work and organ diseases as a result of either desynchronisation or exhaustion
Shift lag solutions research?
- Czeisler - frequent shift change harder to readjust to so longer periods of readjustment (rotating shifts)
- Bambra - quicker shift changes = better health and work life balance (forward rotating shift)
- Boivin - artificial lighting makes it easier to stay awake
- Boivin & James - field study on nurses
Who developed the two exological theories of sleep?
Webb - Hibernation theory
Meddis - Protection theory
Evaluative research of Webb
- Meddis, Pearson & Lanford - 70yo nurse sleeps for 67 mins
- sloths
- Horne - can repair when awake and resting (negative as sleep doesn’t conserve energy)
Evaluative research of Meddis
Pilleri - dolphin sleeps a few seconds at a time as in danger of floating debris
Who developed the two restoration theories of sleep?
- Oswald - SWS needed for repair of body and REM only needed for repair of brain
- Horne - core sleep 4+REM needed for brain repair and SWS1-3 optional
Evaluative research of Restoration Theory
- Peter Tripp (TSD) stayed awake 201hrs = abusive, paranoia and hallucinations (pos)
- Meddis, Pearson & Langford - 70yo nurse sleeps 67mins/day shouldn’t be able to function properly (neg)
- Jouvet (PSD)- cats on flower pots deprived of REM died after 35 days (pos Horne)
Main studies on circadian rhythms?
Siffre cave study
Aschoff & Weber bunker
Czeisler flash light on knees
Evaluative research in lifespan changes?
- US National Institute of Health - explored cot death
- Tynjala et al - compared sleep cycles of teens across culture
- Dement - middle age too busy that they have less time to volunteer
Research into Insomnia?
- Dauvilliers et al - correlation between those with insomnia and insomniac family members (genetics)
- Nofzinger et al - PET scans insomniacs have less decline in brain activity (brain chem)
- Vgontzas et al - increased levels of stress hormones
Research into Narcolepsy?
- Lin et al - narcoleptic dogs have mutations in gene on chromosome 12 (hypocretin)
- Honda - increased frequency of HLA
- Stanford Medical Centre - 90% w cataplexy have HLA variant
- Vogel - REM observed at onset of sleep
How long to circadian rhythms last?
Approximately 24 hours
Give some examples of Circadian Rhythms
Sleep-Wake Cycle, Body Temperature cycle and Metabolic rate cycle
How long do Ultradian rhythms last?
Less than 24 hours
How long do Infradian rhythms last?
Longer than 24 hours
Give an example of an Infradian rhythm
SAD, menstrual cycle
Give examples of Ultradian rhythms
- sleep cycles
- hormone release
- foraging
Main findings of Siffre?
SWS remained between 25-32 hrs but as high as 48 = EP is free running but EZs needed to keep perfect time
Temp cycle remained constant but became desynchronised from sleep-wake cycle
Evaluation of Siffre?
- Case study = low eco validity
- Aschoff & Weber
- doesn’t account for individual differences
- shows light and day have an effect
- artificial light used = EZ
Outline Decoursey’s study
Removed SCN = chipmunks didn’t sleep so made noise and weasels heard and ate them
Shows SCN controls rhythms
Outline Morgan’s study
A hamster was bred to have a 20hr cycle. It’s SCN was removed and put into another hamster who’s rhythm changed to 20hr (SCN controls circadian rhythms)
IDA in reference to endo and exo
- nature (endo) AND nurture (exo) =
- chronotheraputics
Recht et al evaluation?
- not matched on performance = west coast players may just be worse
- may have had a bad nights sleep due to worry
What are the solutions for jet lag?
-Social Customs
Outline Webb’s Hibernation Theory
Sleep = adaptive = conserve energy
Evolutionary hangover
Outline Meddis’ Protection Theory
Sleep = adaptive = keeps is safe
Night time used to be dangerous so sleep is advantageous
What’s an overall disadvantage of ecological theory of sleep?
- doesn’t explain why we have 5 stages
- doesn’t explain psychological problems if deprived (e.g. Tripp)
What are the 4 parts to the evolutionary theory?
Environment - some nocturnal
Sleep site - animals in more exposed locations will sleep less
Size - large animals tend to sleep less
Predator or prey - prey sleep less as are more vulnerable
Why does the evolutionary theory criticise restoration theory?
- reductionist as doesn’t account for these factors
- some animals e.g. Dolphins don’t have REM but are still clever and function adequately
