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Chapter 6 - Consciousness. "Dreaming permits each and every one of us to be quietly and safely insane every night of our lives" -William Dement. Defining Consciousness: The organism’s awareness of, or possibility of knowing, what is happening inside and outside itself.
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Chapter 6 - Consciousness "Dreaming permits each and every one of us to be quietly and safely insane every night of our lives" -William Dement
Defining Consciousness: The organism’s awareness of, or possibility of knowing, what is happening inside and outside itself. Fill in the following blanks as they pertain to the last few hours: I tasted ______. I smelled ______. I saw ______. I touched ________. I heard _______. I remembered _____. I felt ________. I thought _______. These sensations, feelings, and perceptions are processed and sometimes stored and accumulated to form our consciousness. Our consciousness is different at each moment of our lives!
Consciousness is a construct – a concept requiring a belief in something that cannot be seen or touched but that seems to exist. Levels of Consciousness Are we conscious of everything we do? NO. Three Levels: 1. Conscious mind 2. Subconscious mind 3. Unconscious mind Subconscious – consciousness just below our present awareness. • example: “Zoning out” while driving • serves as a filter for the stimuli we are constantly assaulted with. Unconscious
Unconscious – thoughts or desires about which we have no direct knowledge. • Includes intuitive feelings – those not necessarily influenced by logic or reason. Unseen Forces • All creatures are controlled by bodily rhythms and cycles. Types: 1. Day/night – animals/insects 2. Monthly (infradian rhythms)– females and males 3. Annual – humans (weight, energy, and chemical levels) and birds. * Birds respond to light/dark cycle of the earth as winter approaches as their cue to migrate. They use the stars to guide their flight as well as built in magnetic particles that orient them to the earth’s magnetic field so they can stay on course.
Biological Clocks • Internal chemical units that control regular cycles in parts of the body. • Our body temperature is regulated by one of these clocks. Free-running cycles – cycles set up by biological clocks that are under their control, ignoring the environment. example: The kidneys Entrainment – The process of altering the free-running cycle to fit a different rhythm. • The human sleep-wake cycle (ultradian rhythms) can be modified using this method. Example: The human body goes through a natural 25-hour sleep-wake cycle, but the earth moves on a natural 24-hour light-dark cycle. Through the process of entrainment, the human body adapts to this 24-hour cycle.
Circadian Rhythms Sequences of behavioral changed that occur every 24 hours. • Human circadian rhythm is based on a 24-hour cycle that contains within it a high point and a low point. • For most people, the lowest point (low temperature, low blood pressure, and weakness) occurs between 3 a.m. and 5 a.m. http://healthysleep.med.harvard.edu/interactive/circadian
Hypothalamus • Sleep control center in the brain • Monitors changes in light or dark in the environment • Changes levels of hormones in the body
Melatonin • Hormone that helps regulate daily biological rhythms-controlled by the pineal gland which is regulated by the hypothalamus • Linked to the sleep-wake cycle • Melatonin level increases during the day and evening to make us sleepy at night
The Sleep Cycle Beta Waves
Stage 1-NREM Cats nap on and off throughout the day and night. Healthy humans typically have consolidated periods of wakefulness and sleep.
Stage 1-NREM • Alpha waves present • Time distortion-approx. 5 min in length • Hypnic Myoclonia • Hypnogogic/hypnapompic hallucinations • REM replaces stage 1 in all but the first and last sleep cycles
Stage 2-NREM • Sleep spindles • K-complexes • First time through stage 2 lasts about 20 minutes • Approximately 50% of total sleep time
Stage 3-NREM • Beginning delta waves
Stage 4-NREM • Delta waves-slow wave sleep • First time through about 30 minutes • Hardest time to wake the sleeper • Bedwetting • Sleepwalking (somnambulism) • Sleep talking • Night terrors
REM-Rapid Eye Movement "Dreaming permits each and every one of us to be quietly and safely insane every night of our lives" -William Dement • Approximately 20% of sleep time • Paradoxical sleep-brain active, but body essentially paralyzed (brainstem blocks muscle movement) • Nightmares • Necessary part of sleep • REM periods increase as night progresses
Sleep Deprivation Effects • Decreases efficiency of immune system functioning • Safety and accident issues • Contributes to hypertension, impaired concentration, irritability, etc. • Peter Tripp Winston Churchill napped for at least an hour every afternoon during World War II.
Sleep Deprivation Disasters • Sleep deprivation is the culprit for some of the worst human-caused disasters in history. • On top of that, approx 100,000 car crashes are caused due to sleep fatigue which results in 1,550 deaths per year.
Chernobyl • When the nuclear power plant in Ukraine exploded, creating what some have described as the world's worst nuclear disaster, the engineers involved had beenworking for 13 hours or more, MSN reported. Two plant workers died that night. Nearly 240 people were originally diagnosed with radiation poisoning, and 134 cases were later confirmed. Of those confirmed cases, 28 people died during the following few weeks. The number of deaths attributed to the explosion over the next 15 years proved difficult to quantify. "In reality, the actual number of deaths caused by this accident is unlikely ever to be precisely known," the World Health Organization wrote in a 2006 report.
Three Mile Island • Considered to be the most serious nuclear incident on U.S. soil, the accident at Three Mild Island in Pennsylvania was attributed to human error due to sleep deprivation. Between 4 and 6 a.m. on March 28, 1979, shiftworkers didn't notice as the plant lost coolant, eventually resulting in the overheating of the reactor's core, according to the United States Nuclear Regulatory Commission. Officials discovered later than about half of the core had melted, yet there were minimal effects outside of the plant.
The Space Shuttle Challenger • The space shuttle exploded just seconds after its January 1986 launch, killing all seven crew members. According to a 1988 report, certain managers involved in the launch had only slept two hours before arriving to work at 1 a.m. that morning. The Presidential Commission on the accident admitted the danger of this deprivation in its June 1986 report, writing, "The willingness of NASA employees in general to work excessive hours, while admirable, raises serious questions when it jeopardizes job performance, particularly when critical management decisions are at stake."
Exxon Valdez Oil Spill • When the supertanker ran aground in Alaska in 1989, destroying wildlife and spilling 258,000 barrels of crude oil in the process, third mate Gregory Cousins was allegedly sleeping at the helm, leaving him unable to turn the boat back into the shipping lanes in time to avoid disaster. The crew had just put in a 22-hour shift loading the oil onto the ship, the Anchorage Daily News reported, and Cousins had reportedly only had a "catnap" in the last 16 hours leading up to the crash.
American Airlines Crash 1420 • On June 1, 1999, American Airlines Flight 1420 overshot the runway at Little Rock National Airport, killing 11, including the captain, and injuring the first officer, the flight attendants and 105 passengers. Only 24 passengers were not injured. Severe thunderstorms played a role, but the National Transportation Safety Board also determined that "impaired performance resulting from fatigue" was involved.
Theories on why we Dream1. Information-Processing Theory • Dreams serve an important memory- related function by sorting and sifting through the day’s experiences • Research suggests REM sleep helps memory storage.
Theories on why we Dream 2. Physiological Function Theory • Neural activity during REM sleep provides periodic stimulation of the brain.
Theories on why we Dream 3. Activation-Synthesis Theory • Dreams are the mind’s attempt to make sense of random neural firings in the brain as one sleeps.
Theories on why we Dream 4. Cognitive Development Theory • Dreams part of the maturation process • Dreams reflect our knowledge • Reflection of normal cognitive development
Questions about Dreams q. Are there people who never dream? a. Only in special, rare cases. • Dreams are most likely during a phase of sleep called REM (rapid eye movement) sleep. Even people who say they never remember dreams, usually do remember dreams when lab technicians wake them up during REM sleep. The main exception seems to be people with rare kinds of brain damage.
q. How many minutes does it take for the average, normal person to fall asleep? a. 15 - 20 • Of course, this varies from person to person and from time to time. If you consistently fall asleep much faster (say, within 5 minutes, every single night), this could be a sign that you are overly sleepy. If you consistently take more than 30 minutes to fall asleep, you may have insomnia.
q. How many hours of sleep should young people (ages 11 – 17) get each night? a. 9 - 10 • Research shows that young people your age don’t perform their best, and don’t awaken easily without an alarm clock, unless they get close to ten hours of sleep!
q. How many nightmares does the average young adult have in one year? a. 12 • Some people have many nightmares. Others have none. (Psychological tests show nightmare sufferers may be more open, sensitive, and trusting than other people). The frequency of nightmares changes with age. Children aged 3-8 are particularly susceptible to nightmares. The once-a-month figure (above) comes from research on college students. Most nightmares are due to stress, illness, trauma, or physical discomfort.
q. How many dreams does the average person have in one night? a. 3 - 5 This is really a guess. But each night, we typically have 3 – 5 periods of REM sleep. And when scientists wake people up from REM sleep in sleep labs, most of them (80%) report that they were dreaming.
q. Do blind people dream? a. Yes. The dreams of people blind from birth feature sounds, touches, emotions, etc.-just like their waking experience. People who went blind after age 7 usually see some visual images in their dreams.
q.Which animals dream? a. All mammals (except the spiny anteater) • If you have a pet, you have probably seen the animal twitch in its sleep. All mammals experience REM sleep, and research suggests that during REM, they experience the same hallucinations that we humans call dreams. But different species go through the cycles of sleep at different rates. For instance, cats’ REM periods are only 24 minutes apart. Opossums’ REM periods are about 90 minutes apart, the same as ours.
q.Sleepwalking occurs during which type of sleep? • “Slow Wave” sleep / Delta sleep • Most sleepwalking happens during the deepest kind of sleep, Slow Wave Sleep (SWS). Contrary to popular opinion, it is not harmful to wake up a sleepwalker. However, it may be hard to do. People are usually very hard to wake up from SWS.) Kids often outgrow sleepwalking, although the problem can linger into adulthood.
q. Do people dream in color? a. Yes. • People who pay more attention to color in waking life (artists, etc.) are more likely to notice the colors in their dreams. But even people who don’t normally notice color in their dreams are often able to recall specific dream colors under certain circumstances (awakened during REM in a sleep lab, and asked specific color questions by the technician).
q. Is it true that if you die in your dream, you’ll die in real life? a. NO! • It is a common superstition, but a false one. Many people do wake up from dreams or nightmares just before the unavoidable death of their dream-self. Even in our dreams, we have a strong survival instinct; many peoples’ dreaming minds simply will not allow the dream to continue if death seems certain. But some people do dream of their own death and live to tell about it.
q. What percentage of American adults say that they have had a psychic dream? a. 66% • Reports of psychic dreams are amazingly common. Scientists often attribute the reports to chance or coincidence. But those who have experienced these dreams staunchly believe in psychic phenomenon. What do you think?
q.How many major religions have teachings that include Divine/spiritual dreams? a. All. • The Bible mentions quite a few important dreams, as do the sacred texts of all major world religions. Most religions teach that: 1. Dreams can be a way of communicating with a Higher Power. 2. Not all dreams should be regarded as messages from God.
q. What do the following have in common? Pregnancy, psychological trauma, natural awakening (without an alarm clock). a. Increase dream recall. • People who have been through traumatic experiences such as rape, wartime combat, or natural disasters, usually notice that their dream recall increases sharply. The hormonal changes (and/or lighter sleep) of pregnancy also seem to boost dream recall. Some medications can cause a sudden surge of dreams. You are much more likely to remember dreams if you wake up naturally and have an unhurried morning.
q. What do the following have in common? Bright light, warm temperature, cold feet, caffeine, stress. a. Worsen sleep • Even with your eyes closed, some light gets through your eyelids and sends a subtle “wake-up” signal to your brain. When the room is hot, it may cause nightmares. Studies show it takes longer to fall asleep when your feet are cold. Some people feel that caffeine does not affect them much, since they can still fall asleep. But research shows that the quality of caffeinated sleep probably isn’t as good; there are more arousals and restless movements. Caffeine can stay in your system and affect your sleep for 6 hours.
q. What do the following have in common? Waking up at the same time every day, milk & turkey near bedtime, regular “white” noise? a. Improve sleep. • People who maintain very regular sleep schedules of bedtime and awakening times tend to sleep better. Milk and turkey contain an amino acid called tryptophan, which may improve sleep. Some light sleepers benefit by listening to a very consistent noise (such as an electric fan), which may help cover up irregular background noises that might otherwise wake them up.
q. What do the following have in common? Alcohol, marijuana, depression a. Decrease dream frequency • All of these affect REM sleep, and suppress dreams. Oddly enough, some people may actually feel they dream more after having alcohol, for example. Why? Because when our bodies are deprived of REM sleep, they eventually go into “REM rebound,” an intense REM state that tries to “make up for lost time” in that sleep stage. The resulting dream may be more memorable (and/or more disturbing!), but in reality, the body is still not getting enough REM sleep.
q.What do the following have in common? Loss of creative thinking, irritability, slower reaction times, difficulty learning new skills? a. Effects of sleep deprivation • It really is a bad practice to pull “all nighters” before important exams. It affects the way your brain works, and also may affect its ability to store knowledge in an orderly way for long-term retrieval. Your creative thinking and your good mood are usually the first things to suffer!
q. What do the following have in common? Feel awake but unable to move, may sense an “evil presence” in the room, may struggle to breathe. a. Symptoms of sleep paralysis (also called “Old Hag” experience) • People have been describing this phenomenon since ancient times. Scientists have a theory about why it may happen. Ordinarily, during dreaming sleep, our brain sends a chemical message that paralyzes our body (which protects us from acting out our dreams and getting into a lot of trouble!) But sometimes, for unknown reasons, something goes wrong and this protective paralysis doesn’t go away when we first wake up. It’s as if it takes our brain a minute to realize that dreaming sleep has ended. The hallucinations of dreams may continue, too, resulting in visions of evil creatures. Why are visions almost always scary? Because it is very scary to feel helpless and paralyzed, which may trigger us to imagine scenes of malevolent spirits.