Transcript The History and Scope of Psychology Module 1

States of Consciousness
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Biological rhythms
Sleep Cycle
nREM and REM sleep
Sleep theories
The Study of Consciousness
• Does consciousness exist?
– Many psychologists believed it did not.
– Today, many believe it does
• Linked with behaviors (talking) and brain waves
• As a construct
– What is a construct?
• A concept used to talk about something we cannot
see, touch, or measure directly.
• Includes intelligence and emotion.
The Study of Consciousness
• Meanings of Consciousness
– Sensory Awareness
• Your senses make it possible for you to be aware of your
environment.
• Conscious of things outside yourself, but can be unaware of
sensory stimulation.
– Selective listening
– Direct Inner Awareness
• Think of abstract concepts – emotions, memories
– Sense of Self
• Realize existence, unique, separate from source – only after
infancy
The Study of Consciousness
• Levels of Consciousness
– Preconscious – ideas are not in awareness right
now, but could be recalled
– Unconscious (subconscious) – Information is
hidden. Sometimes used as defense mechanism
– Nonconscious – Biological functions (fingernails
growing, pupils adjusting to light)
• Altered State of Consciousness
– Person’s sense of self or sense of world changes
(sleep)
Biological Rhythms
• Periodic physiological fluctuations
• Can affect physiological functioning
• Fall into three main categories
–Circadian Rhythms
–Ultradian Rhythms
–Infradian Rhythms
Circadian Rhythms
• Biological rhythms that occur
approximately every 24 hours
• Example: Sleep-wake cycle
Rhythm of Sleep
Light triggers suprachiasmatic nucleus to decrease
(morning) melatonin from pineal gland
and increase (evening) it at night fall.
Ultradian Rhythms
• Biological rhythms that occur more
than once each day
• Example: Stages of sleep throughout
the night
Infradian Rhythms
• Biological rhythms that occur once a
month or once a season
• Example: Phases of the moon
Biological Rhythms
Biological rhythms are controlled by
internal “biological clocks.”
1. Annual cycles: On an annual cycle geese migrate,
grizzly bears hibernate, and humans experience
seasonal variations in appetite, sleep and mood.
Seasonal Affective Disorder (SAD) is a mood
disorder caused by dark winter months.
How does your body get
you ready for sleep?
• Each of us has an internal clock which runs our
circadian rhythm
• Governed by activity in the hypothalamus
• When it is dark outside, the pineal gland secretes
melatonin, which pushed the body toward sleep
• When the sun rises, our melatonin levels have
dropped and we wake up
• Research shows that our bodies would work on a
25 hour clock.
Sleep Cycle and its Stages
Measuring sleep. About every 90- minutes we pass
through a cycle of five distinct sleep stages.
Hank Morgan/ Rainbow
Awake & Alert
During strong mental engagement brain exhibits low
amplitude, fast, irregular beta waves (15-30 cps). A
person awake in conversation shows beta activity.
Beta Waves
Awake but Relaxed
When eyes are closed, but the individual is awake,
brain activity slows down to large amplitude, slow,
regular alpha waves (9-14 cps). A meditating person
exhibits alpha brain activity.
Sleep Stages 1-2
During early light sleep (stages 1-2) the brain enters a
high amplitude, slow, regular wave form called theta
waves (5-8 cps). A person daydreaming shows theta
activity.
Theta Waves
Sleep Stages 3-4
During deepest sleep (stages 3-4) brain activity slows
down. There are large amplitude, slow delta waves.
Sometimes called delta sleep
Stage 5: REM Sleep
After reaching the deepest sleep stage (4) the sleep
cycle starts moving backward towards stage 1.
Although still asleep, the brain engages in low
amplitude, fast and regular beta waves (15-40 cps),
much like awake-aroused state.
A person in this sleep phase exhibits
Rapid Eye Movements (REM)
and reports vivid dreams.
Typical Night’s Sleep
Paradoxical Sleep
• During REM sleep brain wave patterns
are similar to when a person is awake
• Pulse and breathing quickens.
• REM sleep is sometimes called
paradoxical sleep as one’s physiology is
close to that of being awake but the
brainstem blocks all muscle movement
(active sleep)
Why is REM sleep important?
• In an REM deprivation study an individual is
intentionally awakened at the onset of each
REM phase over a period of days
• The subject is then allowed to sleep normally
• During this time they are likely to spend a great
deal more time in the REM stage
– Called “REM rebound”
– Suggest our body really needs REM sleep and will do
what it takes to get it
– Supported by cognitive development of early years
and need for reduced sleep in later life
Sleep Changes through Life
Review
Why do we sleep?
We spend one third of
our life sleeping.
Jose Luis Pelaez, Inc./ Corbis
If an individual remains
awake for several days
they deteriorate, in
terms of immune
function, concentration
and accidents.
Sleep Deprivation
1. Fatigue and subsequent death.
2. Impaired concentration.
3. Emotional irritability.
4. Depressed immune system.
5. Greater vulnerability.
Sleep Theories
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Sleep Protects: Sleeping in the darkness when
predators loom kept our ancestors out of harms
way.
Sleep Recuperates: Sleep helps restore and repair
brain tissue.
Sleep Helps Remembering: Sleep restores and
rebuilds our fading memories.
Sleep and Growth: During sleep pituitary gland
releases growth hormone. Older people release less
of this hormone and sleep less.
• Dream theories
• Sleep disorders
• Hypnosis theories
Why do we dream?
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Information Processing Theory
Physiological function
Activation synthesis
Cognitive development
Freud’s reasoning
Information-Processing Theory
• Dreams serve an important memoryrelated function by sorting and sifting
through the day’s experiences
• Research suggests REM sleep helps
memory storage. (memory
consolidation theory)
Physiological Function Theory
• Neural activity during REM sleep
provides periodic stimulation of the
brain.
Activation-Synthesis Theory
• Dreams are the mind’s attempt to
make sense of random neural firings in
the brain as one sleeps.
• Our minds make sense of the firing by
creating a story line
• Should sound like Gestalt from
sensation and perception
Cognitive Development Theory
• Dreams part of the maturation process
• Dreams reflect our knowledge
• Reflection of normal cognitive
development
Freud
• Believed dreams offer a safe outlet for wish
fulfillment
• Manifest vs Latent content
• The “Royal Road to the Unconscious Mind”
• Too subjective, too many interpretations
Dream Theories
Summary
Sleep disorders and
problems
Insomnia
• Recurring problems falling asleep or
staying asleep
• Sleeping pills tend to inhibit or suppress
REM sleep; worsen the problem
• Alcohol suppresses REM sleep; also
worsens the problem
• Studies show most people overestimate
how long it took them to get to sleep
Sleep Apnea
• Sleep disorder characterized by temporary
cessations of breathing during sleep and
consequent momentary reawakenings.
• Tend to be loud snorers
• Continuous Positive Airway Pressure machine
Narcolepsy
• Sleep disorder characterized by
uncontrollable sleep attacks
• Person may lapse directly into REM
sleep
• Nervous system getting aroused tends
to trigger the sleep attack
Somnambulism
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Formal name for sleepwalking
Starts in the deep stages of N-REM sleep
Person can walk or talk and is able to see
Rarely has any memory of the event
Night Terrors
• Sleep disorder characterized by high
arousal and appearance of being
terrified
• Unlike nightmares
• Happens during stage 4 sleep; mostly
children
• The children seldom remember the
event.
Other Sleep Disorders
• Bruxism – teeth grinding
• Enuresis – bed wetting
• Myoclonus – sudden jerk of a body
part occurring during stage 1 sleep
–Everyone has occasional episodes of
myoclonus
Is Hypnosis an Altered State of Consciousness?
Courtesy of News and Publications Service, Stanford University
1. Social Influence Theory:
Hypnotic subjects may
simply be imaginative
actors playing a social role.
2. Divided Consciousness:
Theory: Hypnosis is a
special state of dissociated
(divided) consciousness
(Hilgard, 1986, 1992).
(Hilgard, 1992)
Aspects of Hypnosis
1.
Posthypnotic Suggestion: Suggestion carried out
after the subject is no longer hypnotized.
2.
Posthypnotic Amnesia: Supposed inability to recall
what one experienced during hypnosis.
Mimi Forsyth
Both Theories
Drugs
• Drugs and Consciousness
• Groups of psychoactive drugs and
the neurotransmitters they mimic
Drugs and Consciousness
Psychoactive Drug: A chemical substance that alters
perceptions and mood (effects consciousness).
Dependence & Addiction
Continued use of
psychoactive drug
produces tolerance.
With repeated exposure
to a drug, the drug’s
effect lessens. Thus it
takes bigger doses to
get the desired effect.
Withdrawal & Dependence
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Withdrawal: Upon stop taking a drug (after
addiction) users may experience undesirable
effects of withdrawal.
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Dependence: Absence of drug may lead to feelings
of physical pain, intense cravings (physical
dependence) and negative emotions
(psychological dependence).
Psychoactive Drugs
Psychoactive drugs are divided into three groups.
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2.
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4.
Depressants
Stimulants
Hallucinogens
Anti-Psychotic
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Depressants
Depressants are drugs that reduce neural activity and
slow body functions
Most depressants act as an agonist at barbiturate site
on the GABA-A receptor
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3.
Alcohol
Barbiturates
Opiates
Alcohol
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Alcohol affects motor skills, judgment, and
memory… increases aggressiveness reduces self
awareness.
Ray Ng/ Time & Life Pictures/ Getty Images
Daniel Hommer, NIAAA, NIH, HHS
Drinking and Driving
Barbiturates
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Barbiturates: Drugs that depress the activity of the
central nervous system, reducing anxiety but
impairing memory and judgment. Nembutal,
Seconal, and Amytal are some examples.
Depressants
http://opioids.com/timeline
3. Opiates: Opium and its
derivatives (morphine
and heroin) depress
neural activity,
temporarily lessening
pain and anxiety. They
are highly addictive.
Stimulants
Stimulants are drugs that excite neural activity and
speed-up body functions.
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Caffeine
Nicotine
Cocaine
Ecstasy
Amphetamines
Methamphetamines
Caffeine & Nicotine
Caffeine and nicotine increase heart and breathing
rates, and other autonomic functions to provide
energy.
http://office.microsoft.com/clipart
http://www.tech-res-intl.com
Amphetamines
Amphetamines stimulate neural activity, causing
speeded-up body functions and associated energy and
mood changes, with devastating effects.
National Pictures/ Topham/ The Image Works
Ecstasy
Ecstasy or
Methylenedioxymethampheta
mine (MDMA) is a stimulant
and mild hallucinogen. It
produces euphoric high and
can damage serotoninproducing neurons resulting in
permanent deflation of mood
and impairment of memory.
Greg Smith/ AP Photos
Cocaine
Cocaine induces immediate euphoria
followed by a crash. Crack, a form of
cocaine, can be smoked. Other forms
of cocaine can be sniffed or injected.
http://www.ohsinc.com
Hallucinogens
Hallucinogens are
psychedelic (mindmanifesting) drugs that
distort perceptions and
evoke sensory images in
the absence of sensory
input.
Hallucinogens
http://static.howstuffworks.com
1. LSD: (lysergic acid diethylamide) powerful
hallucinogenic drug (ergot fungus) also known
as acid.
2. THC (delta-9-tetrahydrocannabinol): is the
major active ingredient in marijuana (hemp
plant) triggers a variety of effects, including
mild hallucinations.
Hemp Plant
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Dopamine :
• Pleasure and reward Movement, Attention, Memory
• Cocaine, Methamphetamine, Amphetamine
• Virtually all drugs of abuse directly or indirectly augment
dopamine in the reward pathway
Serotonin:
• Mood, Sleep, Sexual desire, Appetite
• MDMA (ecstasy), LSD, Cocaine
Glutamate:
• Neuron activity (increased rate), Learning, Cognition,
Memory
• Alcohol
Gamma-aminobutyric acid (GABA)
• Neuron activity (slowed), Anxiety, Memory
• Anesthesia Sedatives, Tranquilizers, Alcohol
Drugs
Summary
AP info…
• Know the rhythms
• Sleep stages
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Stage 1-awake (alpha)
Stage 2- lasts 5-20 minutes, sleep spindles
Stage 3 and 4- up to 40 minutes, delta waves
REM sleep-paradoxical, alpha waves, dreaming
• Why do we dream? Information-processing,
activation-synthesis, physiological function,
cognitive development
• What neurotransmitters are mimicked by
different psychoactive drugs?
More AP info…
• Hypothalamus triggers the pineal gland to
release melatonin (sleep hormone)
• REM rebound
• Hypnosis (divided consciousness or social
influence???)
• Dreams- manifest and latent content (Freud)
Stage 1
Light sleep; Fantastic images resembling hallucinations
Body relaxes; Hypnogogic sensations: falling, floating
Irregular and small brain waves
5 minutes
Stage 2
Relax more deeply
Sleep spindles – bursts of rapid, rhythmic brain wave activity
Can be awakened without too much difficulty
Clearly asleep; Garbled sleep talking is possible
20 minutes
Stage 3
Transitional stage
Brain begins to emit delta waves (large slow waves associated with
sleep)
Few
minutes
Stage 4
Continual delta waves; Stages 3 and 4 termed slow-wave sleep
Sleep-walking, bed-wetting, night terrors
REM
After Stage 4 goes back to stage 3, then 2, then REM (Rapid Eye
Movement)
Dream here
Heart rate rises, rapid and irregular breathing, eyes dart around,
genital arousal, brain waves rapid and saw-toothed
Motor cortex is active, but brainstem blocks it messages
Muscles EXTREMELY relaxed and little movement
Cannot be easily awakened
Termed paradoxical sleep as internally body is aroused while
externally appears calms
10 minutes
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