Chapter 5: Consciousness Flashcards
consciousness
definition
our subjective experience of the world, our bodies, + our mental perspectives
sleep is a form of ____
consciousness
why do we sleep?
4 reasons
-to rest/rejuvinate; restore strength + conserve energy
-to remember; consolidate + retain memories
-to forget; regulate strength of brain synapses to clean out junk in the brain
-to promote functioning; support immune system/problem solving
circadian rhythm
definition
cyclical changes that occur on a roughly 24-hour basis in manyof our biological processes
-including hormone release, brain waves, body temp, + drowsiness
biological clock
definition
the area of the hypothalamus that’s responsible for controlling our levels of alertness
melatonin
definition
hormones produced by the pineal gland deep within the brain
-strongly associated with the onset of sleep
how is melatonin stimulated?
stimulated during periods of darkness
how is melatonin inhibited?
by light
sleep debt
definition
built up when not enough sleep occurs on a given night relative to the amount you normally require
how many hours of sleep do most of us need?
7-10 hours per night
jet lag
definition
the more time zones passed through, the longer it takes for the body’s clock to reset
late work shifts lead to what problems?
-increased risk of injuries
-fatal accidents
-health problems
2 types of sleep
-rapid-eye movement (REM sleep, active sleep)
-non-rapid-eye-movement (NREM sleep, slow-wave sleep)
what is rapid-eye movement sleep called?
active sleep
REM sleep
definition
-high levels of brain + nervous system activity
-rapid movements of eyes
-intensely vivid dreaming
locus coeruleus
definition
brainstem region responsible for keeping us paralyzed during REM
what is non-rapid-eye-movement sleep called?
slow-wave sleep
NREM sleep
definition
-deepest levels of relaxation
-reduced brain activity
4 principal types of brain waves
-beta
-alpha
-theta
-delta
beta waves
definition
-very rapid
-relatively narrow oscillations during normal wakefulness
alpha waves
definition
-low frequency
-in extremely relaxed wakeful states when eyes are closed
theta waves
definition
produced under conditions of drowsiness + light sleep
delta waves
definition
slower + wider in the deepest levels of NREM sleep
how many stages of sleep are there?
5
stage 1 of sleep: NREM or REM?
-NREM
stage 1 of sleep: what waves?
theta waves
stage 1 of sleep: what occurs?
-sleep onset; light sleep 5-10 minutes
-hypnagogic imagery
-myoclonic jerks
hypnagogic imagery
definition
scrambled, bizarre, dreamlike images that flit in/out of consciousness
hypnagogic imagery
example
images of ghosts/other spirits
myoclonic jerks
definition
sudden jerks of our limbs as if being startled/falling
stage 2 of sleep: REM or NREM?
NREM
stage 2 of sleep: what waves?
theta waves
stage 2 of sleep: what occurs?
-light sleep
-brain activity decelerates, heart rate slows, body temp decreases, muscles relax, eye movements cease
-sleep spindles
-k-complexes
sleep spindles
definition
sudden intense bursts of electrical activity
k-complexes
definition
occasional sharply rising + falling waves
majority of our sleep is in what stage of sleep?
stage 2
stage 3 of sleep: REM or NREM?
NREM
stage 3 of sleep: what waves?
theta + delta waves
stage 3 of sleep: what occurs?
-1st stage of deep/slow-wave sleep
-difficult to awaken
stage 4 of sleep: REM or NREM?
NREM
stage 4 of sleep: what waves?
delta waves predominate over theta waves
stage 4 of sleep: what occurs?
-sleep deepends further
-very difficult to awaken
-slow-wave, deep sleep
to feel fully rested in the morning…
we need to experience deeper sleep throughout the night
children or adults spend more time in deep sleep?
children
what suppresses delta wave sleep?
alcohol