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Transcript
Chapter 5
States of Consciousness
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ISBN: 0-131-73180-7
Copyright © Allyn & Bacon 2007
How is Consciousness
Related to Other Mental
Processes?
Consciousness can take
many forms, while other
mental processes occur
simultaneously outside our
awareness
Copyright © Allyn & Bacon 2007
What Consciousness Does For Us
Restricts our attention
Combines sensation with learning and
memory
Allows us to create a mental model of the
world that we can manipulate
Copyright © Allyn & Bacon 2007
Levels of
Consciousness
Conscious
Preconscious
Unconscious
Copyright © Allyn & Bacon 2007
Levels of
Consciousness
Conscious –
Brain process of which we are aware
Nonconscious –
Brain process that does not involve
conscious processing (e.g. heart rate,
breathing, control of internal organs)
Copyright © Allyn & Bacon 2007
Levels of
Consciousness
Preconscious –
Information that is not currently in
consciousness, but can be brought into
consciousness if attention is called to it
Unconscious –
Many levels of processing that occur
without awareness
Copyright © Allyn & Bacon 2007
What Cycles Occur
in Everyday
Consciousness?
Consciousness changes in
cycles that correspond to our
biological rhythms and the
patterns of stimulation in our
environment
Copyright © Allyn & Bacon 2007
What Cycles Occur
in Everyday
Consciousness?
Daydreaming –
A common variation of consciousness in
which attention shifts to memories,
expectations, desires, or fantasies and
away from the immediate situation
Copyright © Allyn & Bacon 2007
Sleep and Dreaming
Circadian rhythms –
Psychological patterns that repeat
approximately every 24 hours
The sleep cycle involves:
REM sleep
Non-REM (NREM) sleep
REM-sleep deprivation leads to REM
rebound
Copyright © Allyn & Bacon 2007
The Sleep Cycle
Copyright © Allyn & Bacon 2007
The Function of Sleep
Possible functions of sleep include:
• To conserve energy
• To restore the body (neurotransmitters,
neuron sensitivity)
• To build “neural nets” and flush out
useless information from the brain
Copyright © Allyn & Bacon 2007
The Need for Sleep
Over the years, the need for REM sleep
decreases considerably, while the need for
NREM sleep diminishes less sharply
Copyright © Allyn & Bacon 2007
Sleep Debt vs. The Circadian Clock
Sleep debt –
Deficiency caused by not getting the
amount of sleep that one requires for
optimal functioning
Copyright © Allyn & Bacon 2007
Sleep cycle
- Stage 1: The state of transition b/w wakefulness and
sleep, characterized by relatively rapid, low-voltage
theta brain waves
- Stage 2: A sleep deeper than that of stage 1,
characterized by a slower, more regular wave pattern,
along with momentary interruptions of “sleep spindles”:
brief bursts of activity
- Stage 3: A sleep characterized by slow delta brain
waves, higher amplitude, with greater peaks and
valleys in the wave pattern, person is now completely
asleep
- Stage 4: The deepest stage of sleep (delta waves),
during which we are least responsive to outside
stimulation, hard to wake up
Copyright © Allyn & Bacon 2007
Sleep cycle continued
- REM (rapid eye movement) sleep: Sleep occupying
around 20 % of an adult’s sleeping time, characterized
by increased heart rate, blood pressure, and breathing
rate, eye movements, and the experience of dreaming;
- produces EEG patterns very similar to those observed
when the person is alert and awake, even though the
person appears deeply asleep and difficult to wake up
(paradoxical sleep). Rapid eye movement occurs
under closed eyelids. REM is when most dreaming
occurs
- NREM sleep: The stages of sleep not associated with
rapid eye movements and marked by relatively little
dreaming (stages 1-4)
Copyright © Allyn & Bacon 2007
Why We Dream:
A Cross-Cultural Perspective
Folk theories
Scientific approach
• Dreams as meaningful events
• Dreams as random brain activity
Copyright © Allyn & Bacon 2007
Dreams as Meaningful Events
Freud believed dreams served the
following two functions:
• To guard sleep
• To serve as sources of wish fulfillment
Dream content
• Varies by culture, gender, and age
• Frequently connects with recent experience
• May help us form memories
Copyright © Allyn & Bacon 2007
Dreams as Random
Brain Activity
Activation-synthesis theory –
Theory that dreams begin with random
electrical activation coming from brain
stem; dreams are brain’s attempt to
make sense of this random activity
Copyright © Allyn & Bacon 2007
Sleep Disorders
Insomnia –
Involves insufficient sleep, the inability to
fall asleep quickly, frequent arousals, or
early awakenings
Sleep apnea –
Respiratory disorder in which person
intermittently stops breathing while
asleep
Copyright © Allyn & Bacon 2007
Sleep Disorders
Narcolepsy –
Involves sudden REM sleep attacks
accompanied by cataplexy
Cataplexy –
Sudden loss of muscle control that occurs
before narcoleptic sleep attack; waking
form of sleep paralysis
Copyright © Allyn & Bacon 2007
Sleep Disorders
Night terrors –
The screaming of a child in deep sleep,
who, once awakened, has no memory of
what mental events might have caused
the fear
Copyright © Allyn & Bacon 2007
What Other Forms Can
Consciousness Take?
An altered state of
consciousness occurs when
some aspect of normal
consciousness is modified
by mental, behavioral, or
chemical means
Copyright © Allyn & Bacon 2007
What Other Forms Can
Consciousness Take?
Hypnosis
Meditation
Psychoactive drug states
Copyright © Allyn & Bacon 2007
Hypnosis
Hypnosis –
Induced state of altered awareness,
characterized by heightened
suggestibility and deep relaxation
Hypnotizability –
Degree to which an individual is
responsive to hypnotic suggestions
Copyright © Allyn & Bacon 2007
Hypnosis As an
Altered State
Experts disagree about whether
hypnosis involves
A distinct state of consciousness
Heightened motivation
Social processes such as role playing
A dissociate state (Hilgard’s “hidden observer”
view)
Copyright © Allyn & Bacon 2007
Practical Uses for
Hypnosis
Hypnosis can have practical uses for
Researchers
Psychological treatment
Medical and dental treatment
Hypnotic analgesia –
Diminished sensitivity to pain while under
hypnosis
Copyright © Allyn & Bacon 2007
Explaining Hypnosis
- Hypnotized ppl may look and act differently than other ppl. Does
this imply hypnosis is an altered state of consciousness?
- Role Theory: holds that hypnosis is not a state of consciousness;
subjects merely act out a special social role.
Ex: ppl act bizarrely in other situations (sports events or concerts)
that aren’t considered altered states of consciousness
- State Theory: says that hypnosis is a true altered state of
consciousness
Ex: there are subtle differences in the mental processes b/w
hypnotized and un-hypnotized subjects
- Dissociation Theory: says hypnosis is not one specific state by a
general condition where ppl re-organize control of their behavior.
Hypnosis creates dissociation, or a split in consciousness. It’s
considered a social agreement to share control with the hypnotist.
Copyright © Allyn & Bacon 2007
Meditation
Meditation –
Form of consciousness change induced
by focusing on a repetitive behavior,
assuming certain body positions and
minimizing external stimulation
Copyright © Allyn & Bacon 2007
Psychoactive Drug States
Psychoactive drugs –
Chemicals that affect mental processes
and behavior by their effects on the
nervous system
Hallucinogens
Opiates
Depressants
Stimulants
Copyright © Allyn & Bacon 2007
Hallucinogens
Alter perceptions of the external
environment and inner awareness
(also called psychedelics)
• Mescaline
• LSD
• PCP
• Cannabis
Copyright © Allyn & Bacon 2007
hallucinogens
A. Mescaline
- is a natural product of the peyote cactus and
is used ritually (and legally) in some religions
- the “buttons” of the cactus are chewed and the
juice is swallowed and as the nausea subsides,
the experience begins
- can also be synthesized and is distributed
“illegally” in pill form
- the effects of mescaline last maybe 4-6 hours
Copyright © Allyn & Bacon 2007
Hallucinogens
C. LSD (lysergic acid diethylamide)
- is a synthetic substance distributed in small amounts, usually on bits of paper
- depending on dosage, LSD tends to produce a much more intensive and disorienting
experience than mescaline and psilocybin, lasting 10-12 hours with stimulant-like
effects
D. PCP (phencyclidene)
- is a synthetic originally developed for use as an anesthetic; medical use was
discontinued, b/c of the hallucinogenic and other side effects
- illegally manufactured PCP powder, also known as “angel dust” can be ingested in
any form, including smoking and is often combined (cut) with other drugs like
cocaine and other hallucinogens, which is one of the greatest dangers of any illegal
drug: you don’t necessarily know what you’re getting and you might even get
poisoned
- PCP effects tend to be profound and depending upon dosage can last for a couple
days!!
Copyright © Allyn & Bacon 2007
Hallucinogens
E. Marijuana
- is a plant that was once widely cultivated for use in making rope
(hemp); the active ingredient is THC (tetrahydrocannabinol), which
is psychoactively in a class of its own
- THC can also be synthesized and is sometimes, illegally distributed
in pill form. Typically, marijuana is simply dried and smoked
- Hash is a hard paste derived by cooking down marijuana leaves
and flowers and is also smoked
- Regardless of form, however, effects include at low dosages,
relaxation and sedation similar to those of depressants, especially
benzodiazepines
- At high dosages, and also depending upon the quality of marijuana,
effects are somewhat like those of hallucinogens, including
euphoria and mild perceptual distortion, drowsiness, and sleep
- Unlike depressants, marijuana is not physically addictive and is not
thought to cause physical damage, except serious respiratory
problems and diseases associated with smoking
- In other words, marijuana is thought to be a carcinogen like tobacco
Copyright © Allyn & Bacon 2007
Opiates
Highly addictive; produce a sense of
well-being and have strong painrelieving properties
• Morphine
• Codeine
• Heroin
• Methadone
Copyright © Allyn & Bacon 2007
Opiates
A. Opium
- comes from opium poppies and can be smoked in its raw form
- codeine, morphine, and heroin come from opium. Heroin is the
most intense version in terms of the feelings you get from it and its
level of addiction
- heroin users can easily overdose from heroin b/c of its strength and
narrow range of effect
B. Methadone
- is a synthetic narcotic used primarily for treatment of narcotics
addiction, as a substitute. It produces relatively little euphoria, but
the pain and suffering associated with withdrawal is eliminated
Copyright © Allyn & Bacon 2007
Depressants
Slow down mental and physical
activity by inhibiting transmission of
nerve impulses in the central nervous
system
• Barbiturates
• Benzodiazepines
(e.g. Valium)
• Alcohol
Copyright © Allyn & Bacon 2007
A. Alcohol
(0.08 blood alcohol level)
- Alcohol is the most widely used and abused depressant drug.
Depressants also include sedative hypnotics (sleeping pills) such
as barbiturates and minor tranquilizers such as benzodiazepines.
Depressants are usually taken orally, although some abusers
sometimes inject them under the skin.
- is a physically addictive drug that produces tolerance and can
produce severe withdrawal effects ranging from irritability and
inability to sleep, with mild abuse to seizures and heart attacks
and death in the case of sustained, long-term abuse.
- abuse also tends to have physical effects throughout the body,
including destruction of neurons in the CNS and damage to the
liver and other organs. It is also quite possible to overdose on
alcohol and die.
- Psychologically, alcohol may initially produce subjective feelings of
an increase in arousal and energy level, but its main effect on the
CNS is depression
Copyright © Allyn & Bacon 2007
depressants
B. Barbiturates (i.e. Nembutal, Seconal, and “downers”)
- were popularly prescribed as sleeping pills in the 50s and 60s but
much less so today, some used as anesthetics. They produce
similar effects to alcohol and are physically addictive and
potentially dangerous. When taken with alcohol the effects
multiply and are more dangerous.
C. Benzodiazepine tranquilizers (i.e. Valium, Librium, Xanax)
- tend to reduce anxiety and produce feelings of calm, and relaxed
well-being, but also produce sleep when taken enough.
- also physically addictive, like barbiturates, when mixed with alcohol
have a more intense and dangerous effect.
Copyright © Allyn & Bacon 2007
Stimulants
Arouse the central nervous system,
speeding up mental and physical
responses
• Cocaine
• Amphetamines
• Methamphetamine
• MDMA (ecstasy)
• Caffeine
• Nicotine
Copyright © Allyn & Bacon 2007
Stimulants
A. Amphetamines
- are synthetic stimulants that were probably prescribed in the 50s
and 60s for weight control. Today, the only true amphetamine
widely available is illegally made methamphetamine or “crystal
meth” a powder that can be snorted or injected
- also available illegally is ecstasy or “X” which is an amphetamine
derivative with distinctively euphoric effects
- medical use of amphetamines was discontinued b/c they are
physically addictive and can be very damaging to the CNS, which
eventually interferes with concentration, and memory. Even
though they are highly effective appetite suppressants, the person
tends to gain the weight back rapidly if they stop using.
Copyright © Allyn & Bacon 2007
stimulants
B. Cocaine
- stimulant with effects similar to amphetamines was once used as a
local anesthetic and even as an ingredient in Coca-Cola. Cocaine
is a natural substance that comes from the coca plant and is
distributed illegally both in highly refined powder and “rock” form.
- It is consumed by snorting or injecting; the most rapid and intense
effects are obtained by smoking “crack” cocaine, which also
produces intense withdrawal effects and craving.
- Effects on the body can be dangerous, especially if combining with
depressants or narcotics, which can be very dangerous physically
and psychologically b/c of the conflicting effects and the “roller
coaster” ride
Copyright © Allyn & Bacon 2007
End of Chapter 5
Copyright © Allyn & Bacon 2007