Consciousness

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Consciousness

• Consciousness as a social phenomenon
• Consciousness and attention
• Phenomena of consciousness

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Consciousness as a social phenomenon

• Behaviorists Consciousness is not important
• Supernaturalists Consciousness is beyond science
• Cognitivists Consciousness is available to study

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What is the role of consciousness?

• A separate set of functions of the brain?
• An organizing principle for choice?
• A unifying principle for the other functions of
  the mind?
• A basis of communication, with ourselves and with
  each other?

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Consciousness and attention

• The stream of consciousness
• Selective attention
• Dichotic listening and shadowing
• Implicit memory and emotional reactions
• Interpreting ambiguous sentences
• Superimposed videotapes and shapes
• Conscious processing has limited capacity

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What factors focus attention?

• Selective attention (Neisser, 1967)
• Instructions
• Meaning
• Salience
• Novelty (NS habituation)
• Change

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Phenomena of consciousness

• The stream of consciousness Attention
• Altered states of consciousness
• Sleep and dreaming
• Daydreaming and fantasy
• Hypnosis
• Drug-induced states
• Mood states and learning

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The sleep cycle

• Electronic recording EEG, EOG, EMG
• EEG patterns divide sleep into four stages
• 1 a waves, 8 - 12 Hz, low amplitude, moderate
  frequency, similar to drowsy wakefulness
• 2 slower frequency, higher amplitude, plus
• K complexes
• Sleep spindles
• 3 d waves appear, 1-2 Hz, large amplitude
• 4 Dominated by d waves

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REM sleep phenomena

• Stage 1 EEG Paradoxical sleep
• EOG (and corneal bulge) show frequent eye
  movements, as if scanning a visual field.
• EMG shows loss of muscle tonus due to downward
  inhibition of a motor neurons, although muscles
  moving hands and feet may twitch.
• Many brain structures function as if awake.

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More REM phenomena

• SNS is partially activated Increases blood
  pressure, respiration, and heart rate.
• Genital response
• Narrative dreaming

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Dream research

• External stimuli may be incorporated into a
  dream.
• Dream events happen in real time.
• Everyone dreams recall depends on when in the
  sleep cycle you awaken.
• Genital response is independent of dream content.
• Sleep-walking and talking are non-REM.

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Interpretation of dreams

• Manifest content is symbolic of latent desires
  (Freud)
• Activation-synthesis theory cf. incorporation of
  external events into dreams.
• Lucid dreams Have you had one?

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Why do we sleep?

• Restoration, recuperation or repair
• Protection with the circadian cycle
• Circadian synthesis

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More altered states of consciousness

• Daydreams and fantasy Unfocussed
• Meditation Focus and relaxation
• Hypnosis
• Stage hypnosis and trickery
• Social facilitation Against our will or
  voluntary compliance? Orne Evans
• Divided or dissociated consciousness
• Split-brain experience

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Drugs and consciousness

• Drug phenomena
• Tolerance and cross-tolerance
• Physiological dependence
• Withdrawal
• Psychological dependence
• Craving
• Drug families Depressants, Opiates, Stimulants,
  and Hallucinogens

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Drug use and abuse

• Factors contributing to drug abuse
• Medication and self-medication
• Family history Nature and nurture
• Promise of immediate payoff
• Feelings of meaninglessness
• Early experience with drugs
• Societal attitudes to drug use The Ledermann
  curve

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EEG patterns
Stage Wave
b
Awake
1 a
2 k
3 d
1 sec
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EEG patterns...
4 d
1 sec
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Shadowing experiment Neissers selective
attention study