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Psychology of Consciousness
Chapter 4
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Consciousness
I. What is Consciousness?
II. What Happens When We Sleep?
III. What Are Dreams and What Do They Mean?
IV. Is it Possible to Control Consciousness by Using Biofeedback, Hypnosis and Meditation?
V. How do Drugs Alter Consciousness?
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I. What is Consciousness?
• Awareness of the sensations, thoughts, and feelings we experience at a given moment
State of awareness of internal & external
Events
– Waking consciousness
– Altered states of consciousness
Related to activity of the neurons
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II. Sleep
The Sleep–Wakefulness Cycle: Circadian Rhythms
– Internally generated patterns of bodily functions that vary over a ~24-hour period
– Function even in the absence of normal cues
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Circadian Rhythms
Disruptions to the circadian rhythm
– Can lead to thinking less clearly, inattentiveness, and feeling sleepy
– Due to shifting work schedules, jet lag, pulling an “all nighter”
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Circadian Rhythms
Accommodating disruptions to the circadian rhythm
– Change schedule slowly
– Follow normal schedule, rather than trying to adjust to the new time zone
– Get exposure to bright light to
increase wakefulness
– Small doses of melatonin promote sleep
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Sleep Stages
REM and NREM Sleep
1. Studying Sleep
• Electroencephalograms (EEGs)
– Graphically record brain-wave activity through electrodes placed on the scalp and forehead
– EEG waves vary in frequency and amplitude
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EEGs
These differ in frequency:
These differ in amplitude:
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Two Types of Sleep
1. Rapid Eye Movement (REM) Sleep
• High-frequency, low amplitude brain-wave activity
• Systematic eye movements also occur during REM
• REM sleep occurs only after four stages of non-REM (NREM) sleep
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Two Types of Sleep
2. NREM Sleep
– Increasing bodily relaxation
– Slower EEG activity
– Slower heart rate and respiration
– More difficult to awaken as the four stages of NREM sleep progress
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Sleep Stages
• Stages 1-4 Non-Rapid Eye Movement NREM)
• Light sleep. Low amp, mixed frequency. Easily awakened.
• Low amp. Relaxed deeper sleep.
• Slower & high amp, low frequency.
• Delta waves. Most difficult to awaken.
• cycles 30-40 minutes. ( 1, 2, 3, 4, 3, 2, 1).
Stages of Sleep
• Stage 1
– Characterized by rapid, low-amplitude brain waves
• Stage 2– Slower, more regular wave pattern
– Sleep spindles
• Stage 3
– Higher peaks and lower valleys of waves
• Stage 4– Slower and more regular, least responsive to outside stimulation
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REM Sleep
Very different from NREM sleep
Difficult to distinguish from being awake on the basis of physiological measures
People in REM are more difficult to awaken
Sleepwalking can not occur during REM sleep
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REM Sleep
Sleepers are more likely to report dreams when awakened from REM
– Dreams do occur in other stages
– Dreams are more vivid, long-lasting, and detailed in REM sleep
REM Sleep sometimes called paradoxical sleep
– Asleep but aroused
– Small movements, but paralyzed
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Sleep Deprivation
The longer a person is deprived of sleep, the greater the effect will be
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Sleep Deprivation
Chronic neglect of sleep is a common — and dangerous — problem
Can not study total sleep deprivation in humans for ethical reasons
However, rats totally deprived of sleep die
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Why do we sleep?
Because we are tired
• Sleep has a restorative function
• What is “restored” by sleep has not been identified
• Fatigue does not relate directly to sleep
– Bedridden people sleep as much as people on their feet all day
– Heavy exercise has little effect on need for sleep
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Repair & Restoration Theory
Makes repairs, restores digestion, removes waste, restore Norepi & dopamine
– Neural Basis: hypothalamus, forebrain, limbic system, brain stem. Exercises neurons.
– Activation-Synthesis Theory
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Dreams -for-Survival Theory
• Permit one to reconsider and reprocess during sleep information that is critical for one’s daily survival
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Evolution/Adaptation Theory
• Sleep requires less energy and keeps us out of danger
– However, also seems to represent a non-adaptive vulnerability
– Hibernation: Decreases heart rate, brain activity, conserve energy, metabolism, body temp
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Consolidation of Memory
Rehearse or preserve information learned though out the day
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Why do we sleep?
Obviously, no single theory fully explains why we sleep
– Sleep likely serves many functions
– Several theories may be needed to explain it
– Is there a sleep switch?
– What makes people go to sleep and wake up?
– Brain systems in the hypothalamus seem to turn on sleeping and waking
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Sleep Disorders
Dysomnias: Predominantly disturbances in the amount, quality, or timing of sleep.
• NOT DUE TO DRUGS/ALCOHOL, MEDICATION OR GENERAL MEDICAL CONDITION
• DSM IV: Primary sleep disorders
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Narcolepsy
Sudden, uncontrollable episodes of sleep
• People with narcolepsy experience muscle weakness and fall uncontrollably asleep
• Affects about 1 in 2,000 people
• Has a genetic component
• Effective drug treatment has been developed
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Sleep ApneaThe sleeper stops breathing, chokes, then wakens
briefly– Causes airflow to stop for at least 15 seconds
– Loud snoring is a symptom
– Can be life threatening
– Associated with excessive daytime sleepiness, and possibly memory loss, severe headaches,
work-related injuries, SIDS
– Middle-aged, overweight men are at increased risk, but sleep apnea can even affect children
– Several effective therapies that keep the airway clear have been developed
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Insomnia
Difficulty in getting or staying asleep
– Affects as many as 1 in 10 people
– Insomniacs feel listless and tired during the day
– Etiology: stress, anxiety, bad sleep habits, psychopathology, age
– More common in females
– Behavioral treatments for insomnia include relaxation training, thought restructuring, and self-hypnosis
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Hypersomnia
Excessive daytime sleepiness (for at least one month).
- Falls asleep easily w/I 5 min. anytime
- Common with obesity
- Usually treated with stimulants,
antidepressants.
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Circadian Rhythm Sleep Disorder
Mismatch between a person’s sleep wake pattern that is normal with his/her environment
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Parasomnias
Predominant disturbance is an abnormal behavioral or physiological event occurring during sleep
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Nightmare Disorder
• Formerly known as Dream Anxiety Disorder
• Bad dreams
• Repeated awakenings from sleep with detailed recall of frightening dreams.
• Occurs during periods of REM
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Sleep Terror Disorder
Repeated episodes of abrupt awakenings from
sleep, usually with a panicky scream.
Person is difficult to calm. No recollection the next
morning.
– Panic attacks that occur within 60–90 minutes of falling asleep
– They occur in NREM sleep, usually stage 4
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Sleep Terror Disorder
They are not nightmares
– Sleep terrors are common in children between ages 3 and 8
– Cause is not well understood
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Sleep Walking Disorder
Repeated episodes of the person leaving bed & walking about w/o being conscious of the episode or later remembering it
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Sleep Walking Disorder
Runs in families
More common in male children
It tends to decrease with age
Sleepwalkers are in stage 4 sleep
• In stage 4, motor portions of the brain are active
• Cognitive portions of the brain show little activity in this stage
– Person may be confused or startled
upon awakening
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III. Dreams and DreamingWhat is a Dream?
A state of consciousness that occurs during sleep
– Usually accompanied by vivid imagery
– Associated with REM sleep
– Dreams do occur during NREM sleep, but tend to be less bizarre and contain less action imagery
– Most people have dreams every night, but forget them when they do not awaken during or soon after a dream
– More dreaming occurs during the second part of the night
– If we dream in 80% of REM periods, we dream three or four times a night
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Content of Dreams
– Dreams are mostly visual, and most are in color
– Most dreams focus on events and people a person comes into contact with
• Lucid dreaming occurs when one is aware of
dreaming as it happens
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Dream Theories
Psychodynamic Views (Freud)
• Dreams are the “royal road to the unconscious”
• Freud believed dreams expressed desires, wishes, and unfulfilled needs that exist in the unconscious
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Freud
Two types of content
Manifest content
• Consists of its overt story line, characters, and setting
Latent content
• The deeper meaning, usually involving symbolic ideas and wishes
• These wishes might make the person uncomfortable if expressed overtly
Manifest and Latent Content
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Psychodynamic Views
Carl Jung (1875 – 1961)
Three purposes of dreams:
• An attempt to make sense of life’s tasks
• To compensate for unconscious urges
• To predict the future
• Jung asserted dreams give expression to the collective unconscious
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Carl Jung
Collective Unconscious
– Storehouse of primitive ideas and images inherited from our ancestors that is shared by all people
– These inherited ideas and images are archetypes
– Representations of archetypes emerge as dreams
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Modern Approaches
Evidence from neuroscience seen as consistent with Freud’s view that dreams are expressions of the unconscious
Other see similarities with Native American philosophies
• Dreams as a route to empowerment and enlightenment
• Not seen as a separate state of consciousness, but as an altered reality
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Cognitive View
– Dreams reflect the same kind of thinking people do when they are awake
– Dreams express current wishes, desires, and issues the person is dealing with
• Bilingual people dream about things related to the language they used before sleeping
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IV. Controlling Consciousness
Biofeedback: Used to learn to control the activity of the system
Usually uses electronic equipment to measure the status of the system
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Hypnosis
A procedure during which a person’s
sensations, perceptions, thoughts, or
behaviors change because of
suggestions made to the person
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Hypnosis
First used as a treatment in the late 1700s
by Franz Anton Mesmer
His work was discredited, and hypnosis fell into disfavor
Opinions are currently divided on the definition of hypnosis and its uses
James Braid: Father of modern hypnotism
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Is hypnosis an altered state of consciousness?What do you think?
Yes
• People can control physiological processes while hypnotized that they normally can not
• Support from PET scan studies
No
• Some people are more suggestible than others and are simply playing the role of a hypnotized person
• Support from studies in which participants are given motivating instructions
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Meditation
The use of a variety of techniques to produce a
state of consciousness characterized by a sense
of detachment
These techniques include concentration, and restriction of incoming stimuli
However, meditation is not relaxation
• Relaxation is a by-product of meditation
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V. Drugs and Altering Consciousness
• A drug is a chemical substance that alters biological or cognitive processes
– Psychoactive drugs
• Alter behavior, thought, or perception
• Therefore, can affect consciousness
• Properties of Drugs
– Tolerance
• Higher and higher doses of a drug are needed to produce the same effect
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Properties of Drugs
• Dependence
– Occurs when the drug becomes part of the body’s functioning
• Withdrawal
– Occurs when dependence has developed and use of the drug is discontinued
• Addiction
– A combination of tolerance and dependence
Influences
• Psychoactive Drugs
–Influence a person’s emotions, perceptions, and behavior
• Addictive Drugs
–Produce a biological or psychological dependence in the user
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Psychoactive Drugs
Must affect the nervous system
– Most do so by crossing the blood–brain barrier
– Mechanism that prevents some
molecules from entering the brain
Once in the brain, drugs alter neural activity
Effects on the CNS
• Drugs whose effect on the central nervous system causes a rise in heart rate, blood pressure, and muscular tension
–Caffeine
–Nicotine
–Amphetamines
• Methamphetamine
–Cocaine
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Effects on the NS
• Impedes the nervous system by causing neurons to fire more slowly
–Alcohol
• Intoxication
•Binge drinking
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Sedatives/Hypnotics
A class of drugs that relax and calm a user
Can induce sleep at higher doses
Depress neural activity
• Sometimes called sedatives or depressants
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Alcohol
Produces tolerance and dependence
Crosses blood–brain barrier
Depresses brain activity
• Dampens arousal
• Decreases inhibitions
• Slows reaction time
• Form of Depressant Prescribed by physicians to induce sleep or reduce stress
Rohypnol“Date rape drug”
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Sedative–Hypnotics
Tranquilizers
Barbiturates
Opiates
– Derived from the opium poppy
– Opium, morphine, and heroin
– Synthetic opiates
• Oxycodone (Oxycontin) and Hydrocodone (Vicodin)
• Chemically similar and have similar effects
– Medical uses include pain relief
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Opiates
• In the brain, opiates occupy endorphinreceptors
– Neurochemicals manufactured in the brain
– A natural mechanism of pain relief
• Opiates produce high tolerance and dependence in those who use them for pleasure
• Few people given opiates for pain relief in hospitals become addicted
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Stimulants
Drugs that increase alertness, reduce fatigue, and elevate mood states
Also tend to increase blood pressure, heart rate, metabolic rate, and decrease appetite
Act on the peripheral and central nervous systems
All stimulants have tolerance and dependence properties
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Stimulants
Caffeine
Nicotine
– Addictive drug in tobacco
– Does not have strong tolerance properties
– Does lead to strong dependence and unpleasant withdrawal symptoms
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Amphetamines
Also produce strong dependence and tolerance
Produce arousal and alertness
Some people use amphetamines for their appetite-suppressing effects
Continued use can cause altered thoughts
• Unfounded suspicion
• Symptoms similar to schizophrenia
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Cocaine
Increases alertness
Rapidly creates positive feelings
These effects are short-lived, creating an urge to use more
Strong potential for abuse
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Psychedelic Drugs
Affect mood, thought, memory, judgment, and perception
Sometimes called hallucinogens
Alter perception and produce vivid imagery
Their impact varies widely depending on the user and the particular drug
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LSD
Lysergic Acid Diethylamide
– Produces altered visual and auditory perception
– Sometimes causes changes in time and distance perception
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Ecstasy
Methylenedioxymethamphetamine (MDMA)
– Causes massive release of serotonin in the brain
• Produces feelings of well-being and kinship
• This action may be dangerous
– May lead to prolonged problems regulating serotonin levels
– May contribute to depression and memory problems
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Marijuana
The dried leaves and flowering tops of the cannabis sativa plant
Most widely used illicit drug
Reactions vary widely
• Elation and well-being
• Sleepiness
• Paranoia and nausea
• Marijuana affects judgment and coordination
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Marijuana
Produces neither tolerance nor dependence
– But, some people use marijuana to the point that it interferes with their lives
– Seems to create a “psychological” dependence in some
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Hallucinogens
• Produces or changes in the perceptual process
– Marijuana
• Tetrahydrocannabinol (THC)
– MDMA (Ecstasy)
– Lysergic acid diethylamide (LSD)
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Drug Use and Abuse
Legal or over-the-counter medications are often not thought of as drugs
– Leads to underestimating hazards of drugs such as alcohol and tobacco
– Alcohol and tobacco present the biggest drug problem in the United States
• 51% of adolescents are current drinkers and 27% are current smokers
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What is Substance Abuse?
When use leads to negative consequences
When drugs are overused and relied on to deal with everyday life
A person is a substance abuser if:
• The person has used a substance for one month
• Use has caused legal, personal, social, or vocational problems
• The person repeatedly uses the substance even
in situations when doing so is hazardous
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With Dependence
Withdrawal symptoms will occur if use is decreased or stopped
• Withdrawal symptoms are typically the opposite of a drug’s effects
• Typically unpleasant
• Can be stopped by taking more drugs
• Doing so is often considered addiction