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Chapter 6

Chapter 6. States of Consciousness. What is it like to be a bulldog?. We’ll never know Third versus first person perspective Philosopher Thomas Nagel (1974) Consciousness is subjective First person accounts of mental processes

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Chapter 6

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  1. Chapter 6 States of Consciousness

  2. What is it like to be a bulldog? • We’ll never know • Third versus first person perspective • Philosopher Thomas Nagel (1974) • Consciousness is subjective • First person accounts of mental processes • Early psychologists relied on introspection (e.g., structuralists)

  3. Nature of Consciousness • Consciousness • awareness of external events and internal sensations • Many levels of awareness • No awareness • Subconscious awareness • Primary awareness • Altered states of awareness

  4. No Awareness • Unconscious (minimal degree of arousal) • Freud’s concept of unconscious mind

  5. Subconscious Awareness • Sleep and dreams • Example: respond to faint tone

  6. Waking Subconscious Awareness • Lightbulb moment! • creative ideas often “incubate” for some time below awareness • Suddenly “pop out” into awareness

  7. Primary Awareness • “Normal” level of awareness • Uncontrolled versus controlled awareness • Stream of consciousness (William James)

  8. Uncontrolled Awareness • Automatic processes • Require minimal attention • Daydreaming • Creativity and fantasy

  9. Controlled Awareness • Shriffrin and Schneider (1977) • Most alert state of human consciousness • Self-Awareness • metacognition

  10. Altered States of Awareness • Drugs • Trauma • Fatigue • Hypnosis • Sensory deprivation

  11. Brain and Consciousness • The association areas of the cerebral cortex and frontal lobes may be key to understanding consciousness.

  12. Brain and Consciousness • Research by Donald Struss from University of Toronto and Vicki Anderson of the University of Melbourne • Higher levels of consciousness associated with frontal lobes • Lower levels of consciousness associated with hindbrain

  13. Brain and Consciousness • Capgas Syndrome • Anderson, Stuss, & Benson (1979) • Disruption of awareness resulting from frontal lobe damage

  14. Biological Rhythms • Biological rhythms are periodic physiological fluctuations in the body. • Length of biological rhythms varies • 24 hour sleep/wake cycle • average 28 day menstrual cycle

  15. Biological Rhythms • Circadian rhythms are daily behavioural or physiological cycles. • sleep/wake cycle • body temperature • blood pressure • blood sugar level • Change from day to night is monitored by suprachiasmatic nucleus (SCN).

  16. Suprachiasmatic Nucleus

  17. Suprachiasmatic Nucleus (SCN) • SCN synchronizes its own rhythm with the daily cycle of light and dark based on input from the retina. • sleeping problems if totally blind • SCN influences • hypothalamus: temperature • reticular formation: sleep/awake

  18. Accuracy of Biological Clocks • Isolate individuals from all “zeitgebers” (i.e., clocks, calendars, moon, sun) • Research by French scientist Siffre (1972) • Lived in cave for six months • 25 hour day

  19. Accuracy of Biological Clocks • Recent research indicates when exposure to light was controlled, participants judged a day to vary from 24 hours to only a few minutes. • Seasonal Affective Disorder (SAD) • Seasonal form of depression • Common in northern countries such as Canada • treatment includes medication and/or light therapy

  20. Biological Rhythms • Desynchronized biological clocks • jet travel, changing work shifts

  21. Biological Rhythms • Ways to reset the circadian clock • exposure to bright light • consumption of melatonin

  22. Why Do We Need Sleep? • Restoration • Sleep restores, replenishes, and rebuilds an organism’s cells. • Adaptation • Sleep may have evolved to protect organisms from danger. • Animals that serve as food for other animals sleep the least.

  23. Hours of Sleep per 24-Hours

  24. Why Do We Need Sleep? • Growth and brain development • Deep sleep coincides with the release of growth hormone in children. • Memory • Sleep helps the brain store and maintain associations formed during recent waking hours.

  25. Effect of Sleep on Performance • Optimal performance is enhanced by sleeping more than 8 hours a night and reduced by sleeping less.

  26. Adolescents and Sleep • Adolescents sleep an average of 9 hours and 25 minutes when they sleep as long as they like. • 16 to 18 year olds are often sleepier during the day than 13 to 15 year olds • Hormonal shifts with age appear to push the time for wakefulness to an hour later

  27. EEG Recordings During Stages of Sleep Beta waves Alert Awake Alpha waves Relaxed Stage 1 Stage 2 Sleep Stage 3 Delta waves Stage 4 Delta waves Stage 5 REM sleep

  28. Sleep and Neurotransmitters • levels of neurotransmitters sent to forebrain • decrease as sleep begins • reach lowest levels during stage 4 • REM sleep • initiated by rise of acetylcholine • terminated by rise in serotonin and norepinephrine

  29. Sleep and Memory • NREM sleep • Reactivates information learned earlier in the day • REM sleep • Consolidates this information into memory • Carlyle Smith of Trent University • Identified paradoxical sleep window • REM sleep is required for learning

  30. Sleep Cycling Through the Night • Periods of REM sleep recur several times when people sleep • With each cycle • length of REM sleep increase • periods of deep sleep decrease

  31. Sleep and Disease • Stroke and asthma attacks are more common during the night and early morning. • Infectious diseases make us sleepy. • cytokines • Sleep problems afflict most people who have mental disorders.

  32. Sleep Disorders • Insomnia • inability to sleep • a third of Canadians • especially women and older adults • Sleepwalking (somnambulism) • during stages 3 and 4 of sleep

  33. Sleep Disorders • Nightmare • a frightening dream that awakens the dreamer from REM sleep • peak at age 3 to 6 years, then decline • Night terror • a sudden arousal from non-REM sleep and intense fear • peak at age 5 to 7, then decline

  34. Sleep Disorders • Narcolepsy • an overpowering urge to sleep • may fall asleep while talking or standing up • Sleep apnea • stop breathing during sleep • numerous brief awakenings • most common among infants and adults over 65

  35. Dreams • Imputed with historical, personal, and religious significance • Dreams are described at length in more than 70 passages in the Bible. • Gender differences in content • Men: aggression, torso anatomy, sexuality, success • Women: friends, victimization

  36. Freud and Dreams • Dreaming is wish fulfillment. • an unconscious attempt to fulfill needs that cannot be expressed, or go ungratified, in the waking hours • both hopes and fears • Many dreams are combinations of distant early experiences with our parents and more recent events.

  37. Freud and Dreams • Example dream: snake and a king • Manifest content of a dream is the surface content. • contain symbols that distort and disguise the dream's true meaning • Latent content of a dream is the hidden content, its unconscious meaning.

  38. Dreams • Cognitive theory of dreaming • same cognitive processes as when awake • Activation-synthesis theory • dreaming occurs when the cerebral cortex synthesizes neural signals from the lower part of the brain • random brain activity

  39. Hypnosis • A psychological state or possibly altered attention and awareness in which the individual is unusually responsive to suggestions

  40. Brain Imaging Evidence • EEG of hypnotized individuals • Predominance of alpha and beta waves • Hobson of Harvard University • PET and fMRI data indicates differences between hypnotized and non-hypnotized individuals

  41. Hypnosis • Do you think you can be hypnotized? • Individual variations • 10 to 20% very susceptible • 10% or less not susceptible

  42. Four Steps in Hypnosis • 1. Distractions are minimized. • 2. Hypnotist tells person to concentrate on something specific. • 3. Hypnotist tells person what to expect in the hypnotic state. • 4. Hypnotist suggests certain events or feelings.

  43. Hypnosis • Some psychologists believe that hypnosis is a divided state of consciousness • Hilgard told hypnotized students they would not experience pain while one arm was in ice-cold water. • Pressed key with other hand to report pain, but verbally said no pain

  44. Hypnosis • Social cognitive behaviour view of hypnosis • Normal state of consciousness where person behaves the way one thinks a hypnotized person should behave • Nick Spanos (Carleton University)

  45. Applications of Hypnosis • Hypnosis is widely used in psychotherapy, medicine, dentistry, criminal investigations, and sports. • Hypnosis can reduce the experience of pain in some people.

  46. Applications of Hypnosis • Sometimes hypnosis is used to enhance people’s ability to remember. • Under hypnosis some people • remember more specific crime details • misremember more false crime details • Can We Trust Forensic Hypnosis? • See “Critical Reflections” for statistics

  47. Psychoactive Drugs • Drugs that act on the nervous system to alter consciousness, modify perceptions, and change moods. • Drug tolerance is the need to take increasing amounts to produce the same effect.

  48. Trends in Illicit Drug Use

  49. Psychoactive Drugs • Addiction refers to either a physical or psychological dependency, or both. • Physical dependence has occurred if disuse produces unpleasant withdrawal symptoms. • Psychological dependence is the strong desire to repeat use for emotional reasons.

  50. Reward Pathway for Psychoactive Drugs Psychoactive drugs increase dopamine levels in the brain’s reward pathways.

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