Chapter 5: Variations in Consciousness

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Chapter 5 Variations in Consciousness
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Consciousness Personal Awareness

• Awareness of Internal and External Stimuli
• Levels of awareness
• James stream of consciousness
• Freud unconscious
• Sleep/dreaming research

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The ElectroencephalographA Physiological Index
of Consciousness

• EEG monitoring of brain electrical activity
• Brain-waves
• Amplitude (height)
• Frequency (cycles per second)
• Beta (13-24 cps)
• Alpha (8-12 cps)
• Theta (4-7 cps)
• Delta (lt4 cps)

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Table 5.1 EEG Patterns Associated with States of
Consciousness
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Biological Rhythms and Sleep

• Circadian Rhythms 24 hr biological cycles
• Regulation of sleep/other body functions
• Physiological pathway of the biological clock
• Light levels ? retina ? suprachiasmatic nucleus
  of hypothalamus ? pineal gland ? secretion of
  melatonin
• Melatonin and circadian rhythms

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Sleep/Waking Research

• Instruments
• Electroencephalograph brain electrical activity
• Electromyograph muscle activity
• Electrooculograph eye movements
• Other bodily functions also observed

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Sleep Stages Cycling Through Sleep

• Stage 1 brief, transitional (1-7 minutes)
• alpha ? theta
• hypnic jerks
• Stage 2 sleep spindles (10-25 minutes)
• Stages 3 4 slow-wave sleep (30 minutes)
• Stage 5 REM, EEG similar to awake, vivid
  dreaming (first a few minutes, then longer)
• Developmental differences in REM sleep

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The Architecture of Sleep

• How quickly one falls asleep, how long one
  sleeps, how one cycles through the various stages
• Varies from one person to the next
• Each of us has a signature sleep pattern mostly
  shaped by biological factors rather than personal
  habits

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Figure 5.5 An overview of the cycle of sleep
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Figure 5.5 An overview of the cycle of sleep
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The Neural Bases of Sleep

• Brain Structures
• Ascending reticular activating system
• Pons, medulla, thalamus, hypothalamus, and limbic
  system
• Neurotransmitters
• Acetylcholine and serotonin
• Also norepinephrine, dopamine, and GABA

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Figure 5.8 The ascending reticular activating
system (ARAS)
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Why Do We Sleep?

• Hypothesis 1
• Sleep evolved to conserve organisms energy
• Hypothesis 2
• Immobilization during sleep is adaptive because
  it reduces danger
• Hypothesis 3
• Sleep helps animals to restore energy and other
  bodily resources

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Sleep Deprivation

• Complete deprivation
• 3 or 4 days max
• Partial deprivation or sleep restriction
• impaired attention, reaction time, coordination,
  and decision making
• accidents Chernobyl, Exxon Valdez
• Selective deprivation
• REM and slow-wave sleep rebound effect

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Sleep Loss and Health

• Sleep loss can affect physiological processes
• Sleep restriction appears to trigger hormonal
  changes that increase hunger
• Studies have found a link between short sleep
  duration and increased obesity
• Mortality rates are especially high among those
  who consistently sleep over 10 hours

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Figure 5.10. Mortality rates as a function of
typical sleep duration.
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Sleep Problems

• Insomnia difficulty falling or staying asleep
• Narcolepsy falling asleep uncontrollably
• Sleep Apnea reflexive gasping for air while
  asleep
• Nightmares anxiety arousing dreams - REM
• Night Terrors intense arousal and panic - NREM
• Somnambulism sleepwalking

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Figure 5.12 The vicious cycle of dependence on
sleeping pills
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Figure 5.13 Sleep problems and the cycle of sleep
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Dreams and DreamingContent and Significance

• Dreams mental experiences during sleep
• Content usually familiar
• Common themes
• Waking life spillover day residue
• Western vs. Non-Western interpretations

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Figure 5.15 Three theories of dreaming
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Hypnosis Altered State of Consciousness or Role
Playing?

• Hypnosis a systematic procedure that increases
  suggestibility
• Hypnotic susceptibility individual differences
• Effects produced through hypnosis
• Anesthesia
• Sensory distortions and hallucinations
• Disinhibition
• Posthypnotic suggestions and amnesia

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Meditation

• Meditation practices that train attention to
  heighten awareness and bring mental processes
  under greater voluntary control
• Yoga, Zen, transcendental meditation (TM)
• Potential physiological benefits
• Similar to effective relaxation procedures

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Psychoactive drugs

• Narcotics (opiates) pain relieving
• Sedatives sleep inducing
• Stimulants increase CNS activity
• Hallucinogens distort sensory and perceptual
  experience
• Cannabis produce mild, relaxed euphoria
• Alcohol produces relaxed euphoria, decreases
  inhibitions
• MDMA produces a warm, friendly euphoria

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Table 5.3 Psychoactive Drugs Tolerance,
Dependence, Potential for Fatal Overdose, and
Health Risks