sleep and dreams Flashcards
what is a circadian rhythm?
daily biological cycles associates with various characteristics and physiological changes
when does body temperature drop and rise?
when does melatonin drop and rise?
are daily cycles and circadian rhythm the same for everyone? what do people describe themselves as?
no! being functional at different times
that variability in daily cycles might be a function of?
natural selection
there is a belief that circadian rhythm might be?
coded in our genes
what are some factors that may disrupt circadian rhythm?
SAD, jet-lag, daylight savings, shift work, piolets
what does the suprachiasmatic nuclei (SCN) do?
regulates our circadian rhythm
where is the suprachiasmatic nuclei (SCN) located?
hypothalamus
what does suprachiasmatic nuclei (SCN) have a connection to?
the eye
what cues does the suprachiasmatic nuclei (SCN) use to regulate the cycle?
light cues
what does the pineal gland do?
secrets melatonin
how many stages of sleep are there?
5
how often do we cycle through each sleep stage?
every 90 minutes
what is the typical order of the stages of sleep?
1-2-3-4-3-2-REM
when do beta waves occur?
when awake and alert
when do alpha waves emerge?
when relaxed and drowsy
alpha and beta waves are measures of?
frequency
what happens in stage one of sleep?
theta waves (slower then alpha and beta waves)
lasts a few minutes
may experience myoclonic jerks (body jerks)
what happens in stage two of sleep?
muscles are more relaxed
breathing and heartrate slowed
more difficult to wake up
sleep spindles (1-2 second bursts of rapid brain activity)
what happens in stage three of sleep?
regular appearance of delta waves (slow wave sleep, more difficult to wake up)
what happens in stage four of sleep?
delta waves come to dominate in stage four (occur more frequently)
stage three and four occur collectively together in a process known as?
slow-wave sleep
what does REM sleep involve?
involves eye movements
high arousal (heart rate and breathing increase)
brain waves resemble active wakefulness
likely to report dreaming if woken up in this stage