copyright mcgraw-hill, inc. 2010 1 chapter 4 states of consciousness
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Chapter 4States of Consciousness
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The Nature of Consciousness
Sleep and Dreams
Psychoactive Drugs
Hypnosis
Meditation
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Consciousness
William James & Stream of Consciousness
Awareness of external events and internal sensations Metacognition: thinking about thinking Involves cerebral cortex: association areas & frontal lobes
Arousal Physiological state of being engaged with the
environment Determined by reticular activating system
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Levels of Awareness
Higher-Level Consciousness
Lower-Level Consciousness
Altered States of Consciousness
Subconscious Awareness
No Awareness
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Higher-Level Consciousness
Controlled Processes Most alert states of human consciousness
Active focus of efforts toward a goal
Require attention and effort
Slower than automatic processes
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Lower-Level Consciousness
Automatic Processes States of consciousness requiring little attention
Do not interfere with other ongoing activities
Require less conscious effort than controlled processes
Daydreaming Lies between active consciousness and dreaming
Mind wandering is one type of daydreaming.
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Altered States of Consciousness
Mental states noticeably different from normal awareness
Can be produced by: Drugs Fatigue Sensory deprivation Hypnosis
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Subconscious Awareness
Waking Subconscious Awareness Processes just below surface of awareness
Can occur simultaneously along parallel tracks
Sleep and Dreams Lower level of awareness than daydreaming
Some degree of awareness of external stimuli
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No Awareness
May apply to someone . . . knocked out by a blow anesthetized in a deep, prolonged unconscious state
Unconscious Thought (Freud) Reservoir of unacceptable wishes, feelings, and
thoughts beyond conscious awareness
Nonconscious mental processes
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Sleep: Biological Rhythms
Biological rhythms Periodic physiological fluctuations in body “Biological Clocks”
Circadian Rhythms Daily behavioral or physiological cycle Sleep/wake, body temperature, blood pressure, blood sugar
Suprachiasmatic Nucleus (SCN) Small brain structure using retinal input to synchronize its
rhythm with daily light/dark cycle
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Suprachiasmatic Nucleus
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Sleep: Biological Clocks
Desynchronizing the Biological Clock Can get thrown off regular schedules
Jet travel, changing work shifts, insomnia
Resetting the Biological Clock Bright light
Melatonin
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Why Do We Sleep?
Restoration Cellular production, growth, repair
Adaptation Evolutionary value of sleep during darkness
Growth Physical growth and brain development
Memory Consolidation, storage, maintenance
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Sleep Deprivation
Lack of sleep is stressful. Trouble paying attention to tasks and solving problems Decreased brain activity Can influence moral judgment
Yet many of us do not get sufficient sleep. Americans, in general Adolescents, in particular Also, sleep patterns change into middle/late adulthood.
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Stages of Wakefulness & Sleep
Massive electrophysiological changes occur throughout the brain.
Wakefulness Fast, irregular, low-amplitude electrical activity
Sleep Slow, regular, high-amplitude waves
EEG is used to monitor brain’s electrical activity.
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Wakefulness Stages
Beta waves Reflect concentration and awareness Highest in frequency, lowest in amplitude More desynchronous, or inconsistent
Alpha waves Relaxed, but still awake Brain waves slowed down, increased in amplitude More synchronous, or regular
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Sleep Stages 1 and 2
Stage 1 Drowsy sleep Myoclonic jerks, or sudden muscle movements EEG characterized by slow, high-amplitude theta waves
Stage 2 Decreased muscle activity No conscious awareness of environment Theta waves interspersed with sleep spindles
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Sleep Stages 3 and 4
Characterized by delta waves: slowest and highest-amplitude brain waves
Referred to as delta sleep, the deepest sleep Bedwetting, sleep walking, sleep talking
Stage 3 less than 50% delta waves Stage 4 more than 50% delta waves
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REM Sleep
Rapid eye movement (REM) sleep
Active stage during which dreaming occurs Fast wave activity, similar to relaxed wakefulness Likely plays a role in memory
Non-REM sleep Stages 1 through 4
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Stages of Sleep
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Sleep Cycles
One sleep cycle Five stages of sleep
90 to 100 minutes
Recurs several times a night
REM stages become progressively longer.
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Sleep Cycles
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Sleep and the Brain
Reticular Formation Core of brain stem Distinct pattern of neurotransmitter activity during
each sleep stage Plays crucial role in sleep and arousal
Neurotransmitters involved in sleep: Serotonin Epinephrine Acetylcholine
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Sleep and Disease
Stroke and Asthma Obesity and Heart Disease Immune System and Infection
Cytokines
Mental Disorders Depression
Alzheimer Disease, Stroke, and Cancer
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Sleep Disorders
Insomnia Sleepwalking, Sleep Talking, Sleep Eating Nightmares Night Terrors
Sudden arousal from sleep, intense fear Narcolepsy
Sudden, overpowering urge to sleep Sleep Apnea
Individuals stop breathing and awaken to breathe better
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Dreams
Freud: Dreams symbolize unconscious wishes. Manifest content surface content symbolic Latent content hidden content true meaning
Cognitive Theory Dreams as subconscious cognitive processing Lack of attention to roles of brain structures and activity in dreaming
Activation-Synthesis Theory Dreams as result of synthesis of neural signals
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Uses of Psychoactive Drugs
Act on the nervous system to: alter consciousness modify perceptions change moods
Tolerance Increasing amounts for same effect Physical dependence Need / Withdrawal Psychological dependence Strong desire
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Addiction
Physical or psychological dependence, or both
Psychoactive drugs increase dopamine levels in brain’s reward pathways. Ventral Tegmental Area (VTA)
Nucleus Accumbens
Activation of limbic and prefrontal areas of brain
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Reward Pathways in the Brain
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Psychoactive Drugs: Depressants
Alcohol
Barbiturates Nembutal, Seconal
Tranquilizers Valium, Xanax
Opiates Morphine, Heroin
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Psychoactive Drugs: Depressants
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Psychoactive Drugs: Stimulants
Caffeine
Nicotine
Amphetamines (“Uppers”) Crystal meth
Cocaine Crack
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Psychoactive Drugs: Stimulants
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Psychoactive Drugs: Hallucinogens
Also called psychedelic drugs
Marijuana
MDMA (Ecstasy)
LSD (lysergic acid diethylamide)
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Psychoactive Drugs: Hallucinogens
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Hypnosis
Altered state of consciousness, or Psychological state of altered attention/expectation
Nature of hypnosis: The Four Steps Minimizing distractions, maximizing comfort Concentration on something specific Information about what to expect in hypnotic state Suggestion of events or feelings already occurring
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Explaining Hypnosis
Hypnosis as a Divided State of Consciousness “Hidden Observer”
Social Cognitive Behavior View of Hypnosis Cognitive Factors
Attitudes Expectations Beliefs
Social Context
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Meditation
Attaining peaceful state of mind
Mindfulness Meditation For depression, panic attacks, anxiety For chronic pain, stress, psoriasis
Meditative State of Mind Hypnogogic reverie Feeling of wellness Increased activation in basal ganglia and prefrontal cortex Decreases in anterior cingulate