Lecture 14 - Sleep Flashcards
Sleep lab
to see if something is happening during your sleep that’s abrupting your sleep
- monitor brain waves while asleep
- perhaps not getting proper amount of sleep b/c some disruptions
- used for epileptic testing to check brain waves
Sleep purpose
keeps us alive
- we’re best judge if we get enough sleep but sometimes not
Awake
– ALPHA activity, regular, medium frequency 8-12 Hz (more prevalent with eyes closed); BETA activity, irregular, low amplitude 13-30 Hz.
Stage 1
– THETA activity 3.5-7.5 Hz – transition.
- easy to wake up
- starting to fall asleep
Stage 2
– irregular, periods of theta, SLEEP SPINDLES (short bursts at 12-14 Hz – maintenance of sleep), K-COMPLEXES (≈1 per minute).
- little deeper in sleep than stage 1 - still easy to wake up
- people who are recovering alcoholism or drug use have poorly defined stage 2 sleep or those people that have trouble sleeping have problems with this stage
Stage 3
– high amplitude DELTA >3.5 Hz.
Stage 4
– 50% delta activity.
- deep sleep
- difficult to awaken person
Stages 3 & 4
- slow wave sleep.
- sleep talking, walking & night terrors happen here & not during dream sleep
- deep sleep harder to wake up
REM sleep
desynchronized EEG, some theta, rapid eye movements.
body largely paralyzed. (for your benefit)
(dream sleeping - seem real & relatively remembered)
(newborns spend 50% in REM)
90 minute cycle between ___ and ____ sleep.
REM
NON-REM
(rotates through - cycle)
Dreaming
increased cerebral blood flow to visual cortex (visually dominated areas) and decreased to inferior frontal (areas involved in planning of movements)
- protective mech! - level of paralysis, so you don’t act out your dream (ex: fly out window) & hurt yourself
decreased activity (decreased planning, sequencing of events)
increased activity (increased, vivid imagery)
Sleep Disorders - Insomnia
Margaret Thatcher (and Winston Churchill) slept only a few hours a night!
underlying cause – insomnia is a symptom.
medication can be a curse – sleep medication hangover!
sleep apnea – difficulty breathing while asleep (people who snore have brief periods of apnea).
Sleep apnea
– difficulty breathing while asleep (people who snore have brief periods of apnea).
- narrows pipe going down so much so that your brain gets alerted
- at times, palet closes throat & stops O2 going to brain & your brain doesn’t like that so it temporarily wakes you up, so you snort & snore struggle yourself awake to start breathing again
- can happen repeatively during night
- an get v. little sleep b/c every min or so they’re getting woken up by brain b/c not getting O2 they need
Narcolepsy
sleep attack – at inappropriate times (particularly during monotonous or boring conditions).
≈ 2 – 5 minutes.
cataplexy – falling to ground - hypocretin deficiency – dogs.
sleep paralysis and hypnagogic hallucinations (hallucinations during the transitional state between being awake and sleeping) – alien abduction?
Sleep attack
– at inappropriate times (particularly during monotonous or boring conditions). (monotone)
≈ 2 – 5 minutes.
Cataplexy
– falling to ground (kid dancing - happens when kid is excited & fam cheering him on) - hypocretin deficiency – dogs (sleep paralysis at inappropriate times while awake - we go through it at night, REM sleep paralysis)
Sleep paralysis and hypnagogic hallucinations (hallucinations during the transitional state between being awake and sleeping) – alien abduction?
- “awake” but hallucinating, but paralyzed
- think being abducted by aliens b/c they took control over body
- hallucinations combined with paralysis
REM sleep behaviour disorder
acting out! - supposed to be in paralysis like stage
can be quite dangerous – males dreaming their wives are being attacked will hit out at the attacker – sometimes hitting their wives!
women do it too…
- failure to inhibit movement during REM.
- there is a link from REM sleep disorder & PD’s
Slow-wave sleep
usually during stage 4 sleep. (not during REM)
nocturnal enuresis – bedwetting.
somnambulism – sleep walking – different than REM sleep acting out.
pavor nocturnis – night terrors. (screaming)
usually evident in childhood – resolve naturally.
Nocturnal enuresis
bedwetting
Somnambulism
sleep walking – different than REM sleep acting out.
Pavor nocturnis
– night terrors.
Why do we sleep?
brain rest?
only warm-blooded vertebrates exhibit REM.
necessary for survival? – Indus Dolphin. Deal with swift currents (sleep 7 hours a day but in 4 to 60s intervals).
- swims & breathes air so can’t go to sleep in a swift current or else it will drift off or drown
bottlenose dolphin & porpoise sleep one hemisphere at a time!
keeps one hemisphere alert.
- have to breathe air & not sink to bottom so they put half brain to sleep then switch to other
REM
(if we’re denied it 1 night, we’ll try to make up for it in next night)
perhaps slow wave sleep is restorative but REM sleep is important for development (higher portion of REM during stages of development).
consolidation OR clean up? (what we learned for the day)
Largest increase in REM sleep associated with largest increase in performance.
REM sleep increases during exam time. Don’t deprive yourself!
- helps consolidation info there
