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States of Consciousness
Module 18: Waking & Sleeping Rhythms
We are able to process many things at the same time, with much of that information being processed unconsciously.
Unconscious processing is different from Freud’s ideas about the unconscious mind. Freud’s view of the
unconscious described it as a repository of childhood experiences that influenced behavior without our conscious
knowledge. The modern understanding of the unconscious views it as a parallel processing system that enables
us to deal with all sorts of information & stimuli outside of the conscious. This system helps us to be more
cognitively efficient.
There are actually 3 types of body rhythms:
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Circadian rhythms: those that occur once each day. Our circadian rhythm spans 24 hours & is responsible for
our varying levels of arousal throughout the course of a day.
Ultradian rhythms: those that occur more than once each day & include the cycles of appetite & hormonal
release.
Infradian rhythms: those that occur once per month or season & include menstrual cycle
Remember that the hypothalamus is responsible for behaviors & mental processes governed by hormones, such as
eating, sex, & stress responses. This new unit reinforces that idea by showing that yet another behavior governed by
hormones—sleep—is regulated by the suprachiasmatic nucleus, a small section of the hypothalamus.
In contrast to the sleep induced by most drugs, melatonin-induced sleep seems remarkably normal:
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The stages of both non-REM and REM occur at the usual hours & last the usual amount of time.
Most users do not seem to feel drowsy or experience side effects.
Melatonin seems to promote sleep at any time of the day.
Repeated doses at certain times of day or night can alter circadian body rhythms.
The data suggest that melatonin may be helpful for people:
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Who need to sleep during the day (i.e. night shift workers or those who fly across time zones).
Who are taking drugs which inhibit normal melatonin synthesis.
Who are patients with diseases that cause insomnia.
The brain waves people exhibit when they are awake & active are called beta waves. These are high frequency, low
amplitude waves. Theta waves characterize the transition from stage 1 to stage 2. Theta waves are slower, so they have
higher amplitude & lower frequency than alpha waves, the type of waves that are present as we move from relaxation to
deeper sleep.
**Hypnagogic sensations: these are the hallucinations people experience when they are in early stages of sleep. This
term has been known to show up on the AP exam.
The device used to measure sleep waves is the EEG—which you learned about in Mod 5. This device captures the
electrical activity given off by the neurons as they fire action potentials. The speed which the action potentials occur
creates the brain wave patterns seen during wakefulness & sleep. Sleep researchers use other devices during sleep
studies to measure eye movements & muscle activity to gain a better understanding of the physiology of sleep.
Dreams do not usually occur in NREM sleep, but they can & do happen. Have you ever just fallen asleep & started
“dreaming” about something mundane—like walking down the sidewalk or talking with a friend—only to jerk awake
when you dream you trip or fall? This experience can be explained as an NREM dream. Normally in REM sleep, the body
is completely relaxed so people do NOT react physically to their dreams. But, if we dream during NREM, then our bodies
may interpret our dreams as reality & react to them, causing us to jump or startle at our apparent fall. This is a
hypnagogic sensation! Has this happened to you?! Your dream is translated into behavior since you were not fully in
REM sleep!
REM is also known as “emergent stage 1” sleep. As we go through the sleep cycle each night, the body will start with the
twilight sleep of stage 1 & move into deeper, slow-wave sleep patterns. When the body cycles back up to stage 1, it
experiences brain waves like stage 1 again, only this time it is in REM, the most restful sleep. So while it appears that the
body is coming out of sleep every 90 minutes, it is actually cycling into emergent stage 1 or REM sleep.
“Paradoxical sleep” is a good one to know—if you can recall this term as a synonym for REM sleep, you can remember the
nature of this stage of sleep—that brain wave patterns resemble wakefulness, BUT the body is at rest. (It’s paradoxically
because it is illogical for your brain to be so active while it is in such a deep sleep; when we are at our most relaxed
physically, we are experiencing one of our most active times mentally!)
Keep in mind these stages of sleep with info discussed later in this mod related to sleep disorders. People with sleep
disorders experience a disruption in the regular pattern of sleep, making their experience of the sleep patterns vastly
different. People with sleep disorders experience the most disruption with their REM patterns (ME!!!!)
Ok—I know I was sleep deprived last Friday—1/21 (Block 2, you have no idea how bad I was Block 4!!), anyhooo, nothing
tops this extreme example!
Randy Gardner was a high school student in 1969 who attempted to stay awake for as long as possible. He
eventually stayed awake for 11 days, but he experienced frightening symptoms. He developed a heart murmur,
slurred his speech & couldn’t attend to a conversation for more than a few moments. He hallucinated that street
signs were people, & he believed himself to be an African-American football star—even though he was NOT
African-American & did not play football. When people confronted him w/the truth, he called them racist. Once
he began sleeping again, his symptoms disappeared. He was back to his regular sleep pattern within 3—4 days of
ending his marathon of wakefulness.
Ok, here’s another question to ask yourself: Have you ever fallen asleep while you were bored? (Haven’t we all?!) Here’s
what you do not know; boredom actually does NOT cause drowsiness. In fact, boredom causes restless behavior, like
fidgeting or impatience. When people fall asleep while “bored”, it is actually an indication of sleep deprivation. If you
have fallen asleep during a class, you need to be aware that you are NOT getting enough sleep!
Sleep serves many functions, allowing us to process many things at once. We are great multi-taskers when we sleep—
protecting, recuperating, making memories, thinking creatively & growing all at the same time.
Gregg Jacobs & his colleagues report much better success in treating insomnia when a combination of behavioral
techniques is used. Maybe these can help you someday:
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Sleep restriction: do not spend more than 7 hours in bed. Avoid naps, & arise at the same time every morning,
INCLUDING WEEKENDS!!
Stimulus control: go to bed only when sleepy & use bed only for sleep or relaxing activities. If you cannot fall
asleep w/in 20 minutes, stop trying & do something relaxing.
Relaxation response training: use soothing visual imagery, rhythmic breathing, & muscle relaxation to calm
yourself.
Narcolepsy is often treated using powerful stimulants, amphetamines, to keep the patient’s brain from going into the
REM patterns that are most restful. (amphetamines are in Mod 20!)
Some people theorize that sleep apnea is related to SIDS or Sudden Death Syndrome. This occurs when infants seem to
die without cause in their sleep. Parents have be conflicting advice throughout the years to help their children avoid this
problem, like how to position their infants when they sleep.
Some studies have shown a link between Type 2 diabetes & apnea. Diabetic patients are 3x more likely to have sleep
apnea. The link may be correlational rather than causal; that is, being overweight may be a factor in both disorders.
Some cultural differences in regards to dreams!
Stanley Krippner et al compared the dreams of more than 400 Argentinean, Brazilian & American adults:
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Americans tended to dream about animals & food, whereas Brazilians had more sexual & emotional
dreams.
Americans & Argentineans reported more dreams about architecture than Brazilians
Argentineans reported more dreams about aggression & good fortune than the other 2
Americans from different parts of the country differed in dream content:
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Northeasterners have dreams w/images of time, activity, streets & architecture.
Southerners dream of nature, good fortune, emotion & family members.
Westerners dream about architecture, objects, negative emotions & indoor settings
Krippner found some differences between the genders:
 In the U.S. men were more likely to dream about aggression & tools, women were more
likely to dream about children, clothes, food & friendly interactions.
 There were relatively few gender differences in dreams w/in the Latin-American sample.
Other researchers have found that Mexican women’s dreams are significantly more
emotional than men’s.
The activation-synthesis theory of dreams, helps explain why dreams tend to be random & bizarre. Without external
stimulation & information to help organize the signals fired from neurons, the brain does its best to make sense of the
signals. The brain puts the signals together into a story. Often, the stories it puts together don’t make much sense to the
waking mind.
Do you suffer from “sleep bulimia”? do you use the weekend to play catch up on your sleep—or do you become a night
owl during the weekend, staying up extremely late? What effect do you think this has on your daily performance?
What happens when we don’t get REM sleep? Some studies have shown that REM deprivation can lead to confusion,
irritability, & lack of concentration. Others have shown that very few ill effects occur when one is deprived of REM.
Studies in animals seem to indicate that they will behave as though they are acting out dreams when they are REM
deprived. Regardless, when people or animals are deprived of REM, they experience REM rebound , where they will fall
more easily into REM & stay in REM longer than normal.
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