14.1 - Stages of Sleep Flashcards
what is the typical EEG pattern of sleep
is this constant in sleep?
high voltage, slow
no, there are periods dominated by low-voltage, fast waves similar to those found in awake ppl
what are REMs associated with (2)
- periods of low voltage fast EEG activity
2. loss of electromyographic activity in the neck muscles
what are the three standard psychophysiologic bases for defining the stages of sleep
- Electroencephalogram (EEG)
- electrooculogram (EOG)
- Electromyogram (EMG)
what is the first-night phenomenon
the tendency for ones first night in a sleep lab o be rather fitful
what characterizes the preparation for sleep period of brain activity
alpha waves,
what are alpha waves
waxing and waning bursts of 8-12HZ EEG waves
what characterizes NREM 1
low voltage, high frequency signal - similar to but slower than wakefulness
what changes from NREM 1 to NREM 2 and 3
gradual increase in EEG voltage and decrease in EEG frequency
What characterizes NREM2
higher amplitude, lower frequency than NREM1
- K complexes
- sleep spindles
what are K complexes
single large negative wave followed by a single large positive wave (High amplitude wave that goes up then down)
what are sleep spindles?
1.5-3 second waxing and waning burst of 9-15HZ waves
what characterizes NREM 3
predominance of delta waves
what are delta waves
largest and slowest EEG waves, frequency between 1 and 2 HZ
What occurs when sleepers reach NREM 3?
they remain there, then retreat back up to NREM1
what characterizes the non-initial stage1 periods?
Initial stage 1 EEG is not marked y striking electromyographic or electrooculographic changes
- subsequent periods (Emergent stage 1 EEG) are accompanied by REMS and loss of tone in the muscles and body core
How long is each cycle through the sleep stages?
around 90 minutes
what changes in the sleep cycle over the course of the night?
- More time spend inn emergent stage 1
2. less time in others, particularly NREM3
do people tend to wakeup during the night?
yes, there tend to be brief periods of wakening that the person fails to remember
What is NREM1?
Initial stage 1 only!
what is REM sleep (in terms of stages)w
emergent stage 1 only!!
what do we often call NREM3?
slow wave sleep bc fo delta waves
what are all the physiological traits associated with REM sleep (7)
- REMS
- loss of core-muscle tone
- low amp, high freq. EEG
- cerebral activity increases to waking levels in a lot of brain structures
- general increase in the variability of ANS activity
- Extremity muscles twitch
- almost always some degree of penile or clitoral erection
what led Kleitman to conclude that REM was the physiological correlate of dreaming?
outside of loose of tone in core muscles, all other measures suggest that REM sleep episode is emotion charged
what is the support for the association of REM sleep and dreaming? (2)
- 80% of ppl woken during Rem, but only 7% woken during NREM remember their dreams
- dreams recalled from NREM tend to be isolated experiences, dreams recalled from REM tend to take the form of stories
what complicates the association of dreaming and REM? (3)
- dreams are more prevalent in NREM than was assumed
- NREM dreams can be similar to REM dreams
- REM sleep and dreaming can be dissociated
how can we dissociate REM and dreaming>?
- antidepressants - reduce or abolish REM without affecting dream recall
- cortical lesions - abolish dreaming without affecting REM
Explain the Dement and Wolpert study on external stimuli entering dreams
sprayed water on sleeping volunteers in rem sleep
- woke them up a few seconds later
- 14 pf 33 participants incorporated the water into the dream
what pace do dreams run at?
real time, could correctly determine how long they were dreaming between 5 and 15 minutes in 92/111 cases
Does everyone dream? evidence? (2)
possibly, those who report they dont dream have as much REM as others, and when awakened during REM they report dreams less frequently
Are penile erections during dreams always associated with sexual dream content?
No, erectionsn are no more complete during dreams with sexual content, and even babies have REM related erections
Do somniloquy and somnambulism occur during REM?
No,
- sleepwalking occurs during slow wave sleep as during REM muscles are totally relaxed so one can’t move about
- sleep talking has no special association with REM, can occur during any stage but often occurs during the transition to wakefulness
define manifest and latent dreams
Freudian, manifest are the dreams we experience, latent are he real ones the contain whack content
explain the activation-sythesis hypothesis
based on the observation that during REM, may brain-stem circuits become active and bombard he cerebral Cortex With neural information
- info supplied to the cortex during REM is largely random, the dream is the cortex’s attempt to make sense of these random stimuli
