Module 8 Flashcards
(35 cards)
what are two of our biological rhythms
- biological clock
- sleep cycle
what is our biological clock
our biological clock is our circadian rhythm - it is the ability for our bodies to roughly synchronize with the 24 hour cycle of day and night
when do our thinking and memory improve
our thinking and memory improves as we approach our daily peak in circadian arousal
how long are our sleep cycles
each of our sleep systems last about 90 minutes
who discovered REM sleep
Aserinsky
what is NREM-1
non-REM stage 1
what happens during NREM-1
you may experience fantastic images resembling hallucinations - sensory experiences that occur without a sensory stimulus
what is the next transition after NREM-1
NREM-2
what happens during NREM-2
periodic sleep spindles, bursts of rapid, rhythmic brain-wave activity
what is the next transition after NREM-2
NREM-3
what happens during NREM-3
slow wave sleep which lasts around 30 minutes, your brain emits large, slow delta waves and you are hard to awaken
what happens after NREM-3
you fall back into NREM-2 sleep and this is where you will spend half of your night
what is the next transition after returning to NREM-2 sleep
you fall into REM sleep , the most intriguing of the 4 phases
what happens during REM sleep
during REM sleep your heart rate rises, your breathing becomes rapid and irregular, and every half minute or so your closed eyes dart around in momentary bursts of activity
what do these momentary bursts during REM sleep announce
these movements announce the beginning of a dream
how long was science ignorant of REM sleep
science was ignorant of REM sleep until 1952
what happens to the motor cortex during REM sleep
the motor cortex is active but the brain stem blocks its messages, this leaves your muscles relaxed and you are essentially paralyzed and cannot be easily awakened
how does sleep paralysis occur
the immobility during REM sleep may occasionally linger as you awaken from REM sleep producing sleep paralysis
what is REM sleep sometimes called
paradoxical sleep
what is paradoxical sleep
the body is internally aroused, with waking-like brain activity, yet asleep and externally calm
how much time do we spend in REM sleep during an average night
20-25% of an average nights sleep
how does bright light tweak our circadian clock
it activates light-sensitive retinal proteins
how do these light-sensitive retinal proteins control the circadian clock
they trigger signals to the brain’s suprachiasmatic nucleus (SCN) - a pair of grain-of-rice-sized, 10,000 cell clusters in the hypothalamus
how do SCN’s do their job
by causing the brain’s pineal gland to decrease its production of the sleep-inducing hormone melatonin in the morning and increasing it in the evening
