Chapter 7: Consciousness

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Transcript Chapter 7: Consciousness

Consciousness
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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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What is Consciousness?
– A general state of being aware of and
responsive to events in the environment and
one’s own mental processes
– Are mind and body separate?
• Yes: Doctrine of Dualism
• No: Materialism
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• Levels of Consciousness
Unconscious
Asleep
Awake, but on
“Automatic
Pilot”
Alert
Attention
– Altered state of consciousness
• A state of consciousness that is dramatically
different from ordinary awareness
– Metacognition
• The ability to think about and regulate one’s
own thinking
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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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Sleep
Sleep Stages: REM and NREM Sleep
1. Studying Sleep
• Electroencephalograms (EEGs)
These differ in frequency:
These differ in amplitude:
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Sleep Stages
Two types of sleep
a.Rapid Eye Movement (REM) Sleep
• High-frequency, low amplitude brainwave activity
• Systematic eye movements
• Occurs only after four stages of nonREM (NREM) sleep
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Two types of Sleep
b. 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
3. Typical Sleep Cycle
a. Stages
i. Stage 1
ii. Stage 2
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Stages
iii. Slow Wave Sleep
a) Stage 3
Delta Activity
b) Stage 4
Delta Activity
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Typical Sleep Cycle
b. Sequence and Timing
– Sleepers take about 30 to 40 minutes to go
through the four stages of NREM sleep
– They then go from stage 4, back through
stages 3, 2, and 1
– Then they nearly awaken before going into
REM
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Sleep Stages
4. REM Sleep
– Physiologically similar to being awake
– Difficult to awaken from
• Paralysis of the postural muscles
– Vivid, long-lasting, detailed dreams
– Sometimes called
paradoxical sleep
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Sleep
C. Sleep Deprivation
– The longer a person is deprived of sleep,
the greater the effect will be
– Sleep deprivation is comparable to the
effects of alcohol on driving
– Sleep debt is a common—and
dangerous—problem
– Rats totally deprived of
sleep die
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Sleep
F. Sleep Disorders
1. Narcolepsy
• Sudden, uncontrollable episodes of sleep
• Affects about 1 in 2,000 people
• Has a genetic component
• Effective drug treatment has been
developed
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Sleep Disorders
2. Sleep Apnea
–
–
–
–
Causes airflow to stop for at least 15 seconds
Loud snoring is a symptom
Can be life threatening
Several effective therapies that keep the
airway clear have been developed
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Sleep Disorders
3. Insomnia
– Problems in getting or staying asleep
– Affects as many as 1 in 10 people
– Behavioral treatments for insomnia include
relaxation training, thought restructuring,
and self-hypnosis
4. Night Terrors
– Panic attacks that occur within 60–90
minutes of falling asleep
– They occur in NREM sleep, usually stage 4
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Sleep Disorders
5. Sleepwalking
– Runs in families
– Occurs in stage 4 sleep
• Motor portions of the brain are active
• Cognitive portions of the brain show little
activity in this stage
– It is NOT dangerous to wake a sleepwalker
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Dreams and Dreaming
A. What is a Dream?
– A state of consciousness that occurs
during sleep
– Do occur during NREM sleep, but tend to
be less bizarre and contain less action
imagery
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Dreams and Dreaming
B. The Content of Dreams
– Dreams are mostly visual, and most are in
color
– Tend to focus on events and people a
person comes into contact with
– Environmental stimuli that do not awaken
a sleeper are incorporated into dreams
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The Content of Dreams
• Lucid dreaming occurs when one is aware of
dreaming as it happens
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Dreams and Dreaming
C. Dream Theories
1. Psychodynamic Views
a. Freud
• Freud believed dreams expressed
desires, wishes, and unfulfilled needs
that exist in the unconscious
• Two types of content
– Manifest content
– Latent content
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Psychodynamic Views
b. Carl Jung (1875 – 1961)
– Three purposes of dreams
• Make sense of life’s tasks
• Compensate for unconscious urges
• Predict the future
– Dreams give expression to the collective
unconscious - storehouse of ideas and images inherited
from out ancestors
– Archetypes - the actual ideas and images inherited
from our ancestors
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Dream Theories
2. Cognitive View
– Dreams reflect the same kind of thinking
people do when they are awake
– Cross-cultural studies demonstrate life
events affect dream content
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Dream Theories
3. Biological View
• Activation-synthesis theory of dreaming
• Research support
– REM activity is important for memory
– REM initiates cognitive processing, not
vice versa
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Dream Theories
4. Evolutionary View
– Dreams are practice for dealing with real
threats
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Controlling Consciousness
A. Biofeedback
– A process in which people receive
information about the status of a physical
system
– Feedback used to learn to control the
activity of the system
– Uses electronic equipment
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Biofeedback
• It provides awareness of systems people are
not normally aware of (such as heart rate)
– Allows control of physical responses not
normally under conscious control
• Greatest success is in treating chronic
headaches (especially migraines)
• Many benefits are related to relaxation
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Controlling Consciousness
B. 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
• Factors in hypnosis
– Good hypnotic participants have
• Good visual imagery abilities
• High concentration
– Practice
– Suggestibility
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Hypnosis
• Effects of hypnosis
– Not very good at improving memory
• Suggestibility under hypnosis leads to
distorted memories
• Makes recovered memories very
controversial
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Hypnosis
• Uses of hypnosis
– Aids relaxation
– Helps control pain
– Helps people cope with stress and anxiety
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Controlling Consciousness
C. Meditation
– Use of a variety of techniques to produce a
state of consciousness characterized by a
sense of detachment
– Types of meditation:
• Mindfulness
• Concentrative
– Leads to relaxation
– Helps manage heart disease
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Drugs
• 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
– Dependence
– Withdrawal
– Addiction
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Psychoactive Drugs
1. Sedative–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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Sedative–Hypnotics
a.
Alcohol
– Produces tolerance and dependence
– Crosses blood–brain barrier
– Depresses brain activity
• Dampens arousal
• Decreases inhibitions
• Slows reaction time
– Women metabolize alcohol more slowly than
men
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Sedative–Hypnotics
b. Tranquilizers
c. Barbiturates
d. Opiates
– Derived from the opium poppy
– Opium, morphine, and heroin
– Synthetic opiates
• Oxycodone (OxyContin) and hydrocodone
(Vicodin)
• Chemically similar and have similar effects
– Their medical uses include pain relief
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Opiates
• In the brain, opiates occupy endorphin
receptors
– 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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Psychoactive Drugs
2. Stimulants
– Drugs that increase alertness, reduce fatigue,
and elevate mood states
– Also tend to increase blood pressure, heart
rate, metabolic rate, and decrease appetite
– All stimulants have tolerance and
dependence properties
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Stimulants
a. Caffeine
b. Nicotine
– Addictive drug in tobacco
– Does lead to strong dependence and
unpleasant withdrawal symptoms
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Stimulants
c. Amphetamines
– Produce arousal and alertness
– Also produce strong dependence and
tolerance
– 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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Stimulants
d. 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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Psychoactive Drugs
3. 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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Psychedelic Drugs
a. LSD
– Lysergic acid diethylamide
– Produces altered visual and auditory
perception
– Sometimes causes changes in time and
distance perception
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Psychedelic Drugs
b. Ecstasy
– Methylenedioxymethamphetamine (MDMA)
– Causes massive release of serotonin in the
brain
• May lead to prolonged problems
regulating serotonin levels
• May contribute to depression and
memory problems
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Psychedelic Drugs
c. Marijuana
– Most widely used illicit drug
– Reactions vary widely
– Affects judgment and coordination
– May produce “psychological dependence” in
some
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Drugs
B. Drug Use and Abuse
– Alcohol and tobacco present the biggest
drug problems in the United States
• 51% of adolescents are current drinkers
and 27% are current smokers
• Only 6% of the total population are
current users of marijuana
• Only 4% use other illicit drugs
– Indirect effects cause most problems
associated with drug use
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Drug Use and Abuse
• 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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What is Substance Abuse?
• If dependence has developed
– 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 often considered addiction
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What is Substance Abuse?
• Genetic factors in drug use
– Alcoholism is not inherited
– Genetic factors do relate to the metabolism of
alcohol
• These create a genetic predisposition
• Does not automatically lead to
development of alcoholism
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