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Chapter 6 States of Consciousness. States of Consciousness. Consciousness our awareness of ourselves and our environment Selective Attention our awareness focuses on only a limited portion of what we experience cocktail party effect. Attention. Inattentional blindness
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Chapter 6 States of Consciousness
States of Consciousness • Consciousness • our awareness of ourselves and our environment • Selective Attention • our awareness focuses on only a limited portion of what we experience • cocktail party effect
Attention • Inattentional blindness • failure to see visible objects when we are attending to another task • http://www.youtube.com/watch?v=Ahg6qcgoay4 • Conscious attention • can only be in one place at a time
Sleep and Dreams • Circadian rhythm • the biological clock • roughly corresponds to 24-hour day/night cycle • cyclical bodily rhythms • wakefulness • body temperature
Sleep Stages • Cycle through 5 sleep stages every 90 minutes • Stage 1 Sleep • brief stage; sensation of falling • Stage 2 Sleep • 20 minutes; spindles (bursts of brain activity) • Stage 3 Sleep • brief; transitioning to deeper sleep • Stage 4 Sleep • 30 min.; delta (large, slow) brain waves; deep sleep • REM Sleep • 10 minutes; vivid dreams
Sleep Stages • REM (Rapid Eye Movement) Sleep • recurring • becomes longer as night goes on • vivid dreams • paradoxical sleep • externally calm (muscles) • internally aroused (heart rate)
Brain Waves and Sleep Stages • Alpha Waves • slow brain waves of a relaxed, awake state • Delta Waves • large, slow waves of deep sleep • stage 3 and stage 4 • Hallucinations • false sensory experiences • stage 1: may experience hallucination-like images
Brain Waves and Sleep Stages • Sleep • loss of consciousness that is: • periodic • natural • reversible
Awake Sleep stages 1 2 3 REM 4 0 1 2 3 4 5 6 7 Hours of sleep Typical Nightly Sleep Stages
Minutes of Stage 4 and REM Decreasing Stage 4 25 20 15 Increasing REM 10 5 0 1 2 5 6 7 8 3 4 Hours of sleep Typical Nightly Sleep Stages
Sleep Deprivation Are You Sleep Deprived? 1. Need an alarm clock in order to wake up at the appropriate time. 2. It’s a struggle for me to get out of bed in the morning. 3. Weekday mornings I hit the snooze bar several times to get more sleep. 4. I feel tired, irritable, and stressed out during the week. 5. I have trouble concentrating and remembering. 6. I feel slow with critical thinking, problem solving, and being creative. 7. I often fall asleep watching TV. 8. I often fall asleep in boring meetings or lectures or in warm rooms. 9. I often fall asleep after heavy meals or after a low dose of alcohol. 10. I often fall asleep while relaxing after dinner. 11. I often fall asleep within five minutes of getting into bed. 12. I often feel drowsy while driving. 13. I often sleep extra hours on weekend mornings. 14. I often need a nap to get through the day. 15. I have dark circles around my eyes.
Sleep Deprivation • Effects of Sleep Loss • fatigue • impaired concentration • immune suppression • irritability • slowed performance • increased accidents • planes • autos and trucks
Accident frequency More sleep, fewer accidents Less sleep, more accidents 2,800 2,700 4,200 2,600 4000 2,500 3,800 2,400 3,600 Spring time change (hour sleep loss) Fall time change (hour sleep gained) Monday after time change Monday before time change Sleep Deprivation
Why do we need sleep? • Protective • kept our early ancestors from navigating at night • Recuperation • restore and repair brain tissue • Remembering • restore & rebuild memories from the day • Growth • growth hormone released during deep sleep
Sleep Disorders • Insomnia • persistent problems in falling or staying asleep • Natural Remedies • Exercise • Avoid caffeine (including chocolate) • Dimmer lights • Avoid naps • Wake at same time each day • Turn clock away
Sleep Disorders • http://www.youtube.com/watch?v=X2yfUL8uct0&feature=channel • Narcolepsy • uncontrollable sleep attacks • may lapse directly into REM sleep, often at inopportune times • Hypersomnia • 12-14 hours per day plus nap • Fatigue, stressed –out feeling • Rule out medical
Sleep Disorders • Sleep Apnea • intermittently stop breathing during sleep • frequent momentary awakenings • usually unaware of these episodes • Night Terrors • mostly seen in children • appearance of being terrified (fast heart rate) • occur during Stage 4 • not the same as nightmares (which occur during REM)
Sleep Walking/Talking • occur during Stage 4 (non-REM) Sleep • runs in families • more common in childhood • usually harmless • not remembered the next morning
Dreams • Dreams (REM) • images, emotions, and thoughts passing through a sleeping person’s mind • hallucinatory imagery • discontinuities • incongruities • vivid recall: if we are awakened during REM sleep (or right after)
Dreams - Freud • Sigmund Freud-The Interpretation of Dreams (1900) • dreams viewed as wish fulfillment • outlet for otherwise unacceptable feelings
Dreams - Freud • Manifest Content • remembered story line of a dream • includes real experiences from the day • Tetris experiment • Latent (Hidden) Content • underlying meaning of a dream • Freud: uncovering this hidden meaning can help people resolve personal issues
Dreams • REM Rebound • tendency for REM sleep increases following REM sleep deprivation • Why do we dream? • Freud: outlet for unacceptable feelings • Not supported by research • Information processing: to help “file” memories • Link between REM & memory confirmed by brain scans
Hypnosis • Hypnosis • one person (the hypnotist) suggests to another (the subject) that certain perceptions, feelings, thoughts or behaviors will spontaneously occur • Depends on the subject’s openness to suggestion
Hypnosis • Posthypnotic Amnesia • supposed inability to recall what one experienced during hypnosis • induced by the hypnotist’s suggestion • Memory Recovery • Research has not supported the claim that hypnosis recovers memories that are always accurate • Testimony based on hypnosis is often banned
Hypnosis • “Acid” Study (Orne & Evans, 1965) • hypnotized subjects told to plunge hand into “acid” & throw it in researcher’s face • Next day: denied they would follow such commands • control group: told to “pretend” they were hypnotized • unhypnotized subjects performed the same acts as the hypnotized ones
Hypnosis • Unhypnotized persons can also do this
Hypnosis • Posthypnotic Suggestion • suggestion to be carried out after the subject is no longer hypnotized • used by some clinicians to control undesired symptoms and behaviors • has been found to be helpful for treatment of obesity • addictions (drug, alcohol, smoking) do not respond as well
Hypnotic Pain Relief • 2 Theories • Dissociation • a split between different levels of consciousness • example: “ice bath study” - dissociate the sensation of cold from the emotional suffering we define as painful • Selective Attention • hypnosis doesn’t block sensory input, but it may block our attention to painful stimuli
Hypnosis • Hypnosis as a social phenomenon: • normal state of consciousness • subjects feel and behave in ways appropriate for “good hypnotic subjects” • Hypnosis as divided consciousness • most researchers believe there is more to it than just being a “good subject” • sometimes subjects carry out behaviors even if they think no one is watching • brain activity – areas light up as though subjects are really seeing a color
Attention is diverted from an aversive odor. How? Divided-consciousness theory: hypnosis has caused a split in awareness Social Influence theory: the subject is so caught up in the hypnotized role that she ignores the odor Hypnosis • Divided Consciousness or Social Phenomenon?
Drugs & Consciousness • Psychoactive Drugs • chemicals that change perceptions & moods • Tolerance • brain adapts chemistry to offset drug effects • increasingly larger doses are needed to get the effect • Withdrawal • discomfort following the discontinuation of a drug
Dependence & Addiction • Physical Dependence • indicated by physical pain and craving when the drug is absent • Psychological Dependence • not physically addictive, but user has a psychological need to use the drug • stress-relieving drugs • Addiction • compulsive drug craving and use
Addiction Myths • Addictive drugs quickly corrupt (False) • In most cases addiction does not occur when drugs are used medically • Example: Those given morphine to control pain do not crave the drug like addicts who use morphine to change their mood • Even with highly addictive drugs (cocaine) only some people (about 15%) become addicted • Therapy is required to overcome addictions (False) • Therapy & group support is helpful, but people do also recover on their own
Psychoactive Drugs • Three Categories • Depressants • Stimulants • Hallucinogens • All work at the brain’s synapses • Stimulate, inhibit, or mimic neurotransmitter activity • Our expectations also play a role
Depressants • Reduce neural activity • Slow body functions • Examples: • Alcohol • Barbiturates (tranquilizers) • Opiates
Depressants - Alcohol • Slows reaction times • Speech slurs • Lowers inhibitions • Feelings of invincibility • Disrupts processing of recent experiences into long-term memories • Blackouts result partly from the suppression of REM sleep • Prolonged & excessive drinking can affect cognition (brain shrinking)
Depressants - Barbiturates • Tranquilizers • Mimic the effects of alcohol • Depress nervous system activity • Prescription barbiturates used to induce sleep or reduce anxiety • Can be lethal if taken with alcohol or in large doses
Depressants - Opiates • Opium and its derivatives • Morphine; Heroin • Depress (slow down) neural activity • Lessen pain and anxiety by creating a sense of pleasure • Pleasure is short term and another dose may be craved • Larger and larger doses are needed • Withdrawal symptoms can be extreme • Increasing dose can lead to overdose death
Stimulants • Excite neural activity • Speed up body functions • Examples: • Caffeine • Nicotine • Amphetamines • Methamphetamine (“speed”) • Cocaine • Ecstasy
Stimulants - Cocaine • Enters bloodstream quickly • Rush of euphoria • Brain’s supply of dopamine, serotonin, & norepinephrine are depleted • Crash 15-30 minutes later as drug wears off • Many regular users do become addicted • May lead to: emotional disturbances, suspiciousness, convulsions, cardiac arrest
Stimulants - Ecstasy • A synthetic stimulant • Also a mild hallucinogen • Triggers release of serotonin and blocks its reabsorption • Prolonged feeling of euphoria • Risks: dehydration, overheating, death • Long-term: damages neurons that make serotonin (permanent depressed mood)
Hallucinogens • Hallucinogens • distort perceptions • evoke sensory images in the absence of sensory input • can be natural substances (marijuana) or synthetic (LSD or Ecstasy)
Hallucinogens - LSD • lysergic acid diethylamide • created & accidentally ingested by a chemist • perceived striking images and intense patterns of colors • chemically similar to serotonin • produces a variety of emotions • panic • detachment • euphoria
Hallucinogens - Marijuana • THC – major active ingredient • Mix of effects (difficult to classify drug type) • Relaxes, disinhibits, euphoric feelings • Mild hallucinogen: increased sensitivity to colors, sounds, tastes, and smells • By-products stay in body for 1 month+ • regular users need lower doses for same effect • Amplifies current state (e.g., anxiety or depression)
Hallucinogens - Marijuana • Impairs: • motor coordination • reaction time (makes machine operation unsafe) • formation of memories • information recall • Marijuana smoke • Can be toxic • Lung damage
Drug Use Influences • Biological Factors • Adopted individuals more susceptible to alcoholism if one or both parents have history • Genes identified that are more common among people predisposed to alcoholism • Psychological Factors • Feeling that life is meaningless • Stress • Psychological disorders (e.g., depression)
Drug Use Influences • Social-cultural influences • peer influence • cultural attitude toward drug use • urban environment