Chapter Eight Flashcards
Electromyogram
EMG; records muscle tone
Electro-oculogram
EOG; eye movement
Electroencephalogram
EEG; electrical activity of brain
How many sleep cycles do you go through in a typical night of sleep?
about five
How long does it take to get through one cycle of sleep?
about an hour and a half
Stage One of sleep
10 minutes; theta waves; easily woken up
Stage Two of sleep
K complex; sleep spindles
What are sleep spindles?
thought to be a by product of brain that becomes active during stage two of sleep; filters out distractions/noises that wake you up
Stage 3/4 of sleep
delta waves; stage four is deepest; “slow wave sleep”; most early in the night
which stages does Non-REM take place?
stages 1-4
Does REM get longer with each entry into REM?
Yes
What increases during REM?
eye movement; the 6 eye muscles are the only muscles that move during REM
What happens to muscle tone during REM?
It is lost
What happens to cerebral blood flow during REM?
it increases
How much dreaming occurs during REM?
about 85% (15% nREM)
Refractory period of REM
once awakened, cannot reenter REM for 90 mins; suggests an internal clock regulates this process
Restorative reason for sleep
we need sleep to restore us mind and body; mentally and physically
Cognitive reason for sleep
we need to sleep in order to form memories; brain needs to be removed from constant stimuli
Evolutionary reason for sleep
all humans do this so it must be important. seen as adaptation to benefit survival
Fatal Familial Insomnia
genetic; damage to regions in or near the thalamus
What are the symptoms of fatal familial insomnia?
insomnia, confusion, loss of autonomic NS
What is the life expectancy for fatal familial insomnia?
12 mos. after diagnosis; usually diagnosed in adulthood- mid thirties to forties
What happens to lab animals with lack of sleep?
They will die; prior to death they develop other problems
Complete sleep deprivation
miss one whole night of sleep
Partial sleep deprivation
person sleeps every night but not as much as they should or need
REM deprivation
allow a person to sleep except during REM
Slow wave sleep
allows brain to rest
REM rebound effect
will enter REM more quickly with deprivation; get more REM when deprivation stops
Deprived animal
will lose up to 90% of sleep