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
rem sleep typically involves sleep paralysis, what is it?
muscle activity in inhibited
what is the REM rebound?
as we experience less sleep, intervals of time spent in rem increase (suggesting rem sleep is important)
what is the restoration model of sleep?
sleep ‘recharges’ body, allowing recovery from mental/physical fatigue
what are evolutionary/circadian models? what is an example?
the adaptive function that sleep provides; conserving energy due to the lower metabolic rate while sleeping
what is some evidence for the restoration model?
we sleep longer on days we exert more energy
what does the two-factor model draw on?
draws on elements of both restoration and evolutionary/circadian rhythm
what happens in memory consolidation?
many replay various activities that happened in the day during sleep
what happens to sleep as we age?
we need less, time spent as REM sleep declines
what sleep stage do infants spent the most time in?
REM
what stages of sleep can dreams occur in?
all of them !!
when are we more likely to dream?
when the brain is more active in REM sleep
what is the problem solving dream model?
dreams are an attempt to work through conflicts, issues and problems that we are currently facing in our daily lives
what is the cognitive-process dream theory?
dreams are simply an extension of our normal waking state, with many of the same properties
what did freud’s psychoanalytical theory view dreams as?
a source of wish fulfillment
what is manifest content?
superficial element, manifested in a dream
what is latent content?
meaning (symbolism)
what is the activation synthesis theory?
dreams as a byproduct of the neural activation that occurs in response to sensory stimuli as we sleep
(our cerebral cortex tries to make sense of this seemingly ‘random’ patterns of activation by creating a dream that fits as closely as possible)
what is an example of activation synthesis theory?
a really quiet alarm clock or microwave beeping might act as a fire alarm in your dream
what is insomnia? what causes are we associated with?
chronic difficulty in falling asleep or staying asleep. associated; can be due to genetics, depression, anxiety, etc
what are pseudo-insomniacs?
they believe they have insomnia but sleep relatively normally
what is narcolepsy? what sleep stage does someone immediately go into?
unpredictable and uncontrollable sleep attacks, typically leading someone to go directly into REM sleep
what are the components of sleep walking?
typically occurs in stage 3 or 4
more common in children, who often grow out of it
many possible causes
many possible treatments
what is REM-sleep behavior disorder characterized by?
characterized by a lack of the typical muscle paralysis that usually accompanies REM sleep dreamers can act out their dreams
risking injury to themselves and others
