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Is All Thinking Unconscious?

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Title: Is All Thinking Unconscious?


1
Is All Thinking Unconscious?
2
Jackendoffs Theory
  • Ray Jackendoff
  • Cognitive Scientist
  • Tufts University (with Daniel Dennett)
  • Intermediate Level Theory of
  • Mental Representation
  • Consciousness and the
  • Computational Mind (1990)
  • Thinking is an unconscious process.

3
Three levels of mental representations
  • The external level
  • Specialized modules of perception (vision,
    hearing, taste, etc.), proprioceptive system
    (perception of body states) and motor system
  • Informationally encapsulated and inaccessible to
    consciousness
  • Only the results of perceptual faculties become
    available to consciousness

4
  • 2) The internal level
  • The inner core
  • The location of thought and understanding
  • Operates through the manipulation of
    non-imagistic conceptual structures, i.e. symbols
    with semantic content (via mentalese)
  • Where syntax is processed, spatial relationships
    are understood, music is understood
  • Completely inaccessible to awareness

5
  • 3) The intermediate level
  • The only level that is conscious.
  • Images received from perceptual modules, or
    memory or translated from thoughts generated in
    the inner core.
  • Images include visual images, auditory images
    (primarily words), and sensory images (e.g.
    tastes, smells, bodily sensations).
  • These images are the only mental representations
    available to consciousness.
  • Consciousness consists only of images of
    thoughts.
  • Images of thoughts are distinct from thoughts
    themselves.

6
The Intermediate-Level Theory of Mental
Representations
7
Summary of Jackendoffs Theory
  • Thoughts are formed unconsciously.
  • After they are formed unconsciously, they are
    translated into imagery, i.e. a thought is formed
    in mentalese, then translated in natural language
    and the phonetic form of the thought (the sound
    of the words) is projected into consciousness.
  • We become aware of our thoughts only in phonetic
    form and only after this sound image (or visual
    image, etc.) is projected into consciousness.
  • You can become aware of your thoughts in the form
    of words, or pictures, or even smells,
    sensations, etc., but you cannot become aware of
    your thoughts in their original non-imagistic
    form.

8
Why does Jackendoff believe this?
  • All thoughts are images.
  • We cannot be aware of anything except mental
    images.
  • But, images of thoughts thoughts
  • Evidence for mentalese
  • Ambiguity in imagery (verbal, pictorial)
    ambiguity of meaning
  • Tip-of-the-tongue phenomenon
  • Translatability of propositions
  • Similarities among natural languages

9
Reasons continued
  • Introspective evidence thoughts pop into your
    head. You cannot catch yourself thinking,
    deciding, etc.
  • How do you decide?
  • You are aware of options.
  • You are aware of reasons.
  • You make an unconscious calculation.
  • You are aware of decision.
  • You cannot introspect the unconscious
    calculation.
  • You are only aware of the effect of the
    calculation (i.e. you are aware of the thought
    after it occurs).

10
Wegners Illusion of Conscious Will
  • Daniel Wegner
  • Psychologist
  • The Illusion of Conscious Will (2002)
  • The minds best trick how we experience
    conscious will (2003)
  • Conscious will is an illusion.

11
Illusions of conscious will
  • Three ways in which the experience of conscious
    will can be wrong
  • Someone thinks they have not caused an action
    that they actually have caused.
  • Someone thinks they have caused an action that
    they actually havent caused.
  • These two show double dissociation the feeling
    of having willed an action can be doubly
    dissociated from actually having caused an
    action.
  • 3) Confabulation someone is mistaken about how
    they have caused an action

12
  • Someone thinks they have not caused an action
    that they actually have caused (illusion of
    non-control)
  • Many examples
  • Delusion of alien control
  • - a type of schizophrenia
  • - patients think that an alien, God, devil or
    the FBI is
  • controlling their actions
  • Dissociative Identity Disorder
  • - also called Multiple Personality Disorder
  • - actions are attributed to another personality
    occupying
  • the same brain

13
  • Alien hand syndrome
  • sometimes occurs in split-brain patients
  • (Split-brain patients have had the corpus
    collosum connecting the left and right hemisphere
    of their brain cut drastically reducing
    communication between the two hemispheres)
  • also occurs in non-split brain patients
  • patient has no control over one hand
  • alien hand can conduct complex voluntary
    actions, such as unbuttoning a shirt, moving a
    chess piece, grabbing a cigarette or trying to
    strangle the patient

14
  • Automatisms
  • Complex voluntary actions produced with no sense
    of will and attributed to spirits or other
    strange forces
  • E.g.
  • Spirit possession
  • Dowsing
  • Table turning
  • Ouija board writing

15
  • Someone thinks they have caused an
  • action that they actually havent caused
  • (illusion of control)
  • I-Spy study
  • Participants were set up at a computer looking
  • at a picture of many random objects and sharing
  • a mouse with a confederate
  • Meanwhile, they heard words over a headphone.
  • When they heard a certain word (e.g. swan), the
    confederate gently forced them to stop on a
    picture of that object (e.g. swan)
  • When asked, participants often said they chose to
    stop at the swan.
  • When not forced, participants did not generally
    stop at the object they heard over the headphones
  • Conclusion participants thought they had willed
    an action that they had not.

16
  • 3) Confabulation
  • Confabulation occurs when people are wrong about
    why they performed an action.
  • They come up with a reason for acting, but they
    do not know the true cause of their action.
  • e.g. I hypnotize you to stand up at 300. At 300
    you stand up. I ask you why you stood up. You
    say, you needed to stretch your legs.
  • Shows that people are not aware of their true
    reasons for acting, but still feel that they are
    acting freely for rational reasons.
  • Occurs in cases of hypnosis and direct brain
    stimulation, and in split brain patients.
  • Maybe occurs in normal people all the time.

17
Is Conscious Will Generally an Illusion?
  • These cases show that we are often wrong when we
    think that our conscious thought has caused an
    action.
  • We may always be wrong.
  • Two possibilities
  • The experience of conscious will is unreliable.
  • We normally consciously will our actions, and
    our feeling of having willed an action is
    generally correct, but sometimes the feeling of
    conscious will is an illusion.
  • 2) The theory of apparent mental causation
  • The experience of conscious will is always an
    illusion. Conscious thoughts do not cause
    actions.

18
  • Wegner makes a spectrum of claims
  • From The minds best trick how we experience
    conscious will
  • Does this mean that conscious thought does not
    cause action? It does not mean this at all The
    point made here is that the minds own system for
    computing these relations provides the person
    with an experience of conscious will that is no
    more than a rough-and-ready guide to such
    causation (Wegner 2003).
  • From The Illusion of Conscious Will
  • The fact is, it seems to each of us that we have
    conscious will. It seems we have selves. It seems
    we have minds. It seems we are agents it is
    sobering and ultimately accurate to call all this
    an illusion (Wegner 2002).
  • All feeling of doing is an illusion (Wegner
    2002).

19
Conscious Will is always an illusion
Wegners boldest claim. Actions usually follow
conscious thoughts. Hence we conclude the
thoughts cause the actions. We think, Ill have
a piece of candy, then we eat a piece of
candy. But the causal relation is an
illusion. Common fallacy post hoc propter hoc
-- if A follows B, B caused A. Also possible A
and B have a common cause.
20
The Theory of Apparent Mental Causation
  • Unconscious thought produces conscious thought.
  • Unconscious thought produces action.
  • Conscious thoughts and actions have common cause
    unconscious mental processes.
  • Unconscious processes also produce the feeling of
    having consciously willed an action.
  • Conscious willing of actions is an illusion.

21
How the illusion is generated
22
  • Benjamin Libet
  • Neuroscientist at
  • University of California
  • Died July 2007, age 91
  • Two important sets of experiments in 1970s on
    consciousness of sensations and consciousness
    of decisions to act
  • Controversial experiments support Jackendoff
    and Wegners theories.

23
Libets Experiments
  • Set One
  • Backward Referral of Sensations
  • Set up
  • Performed on patients undergoing open brain
    surgery
  • Libet stimulated their brains and their hands
    with electrodes, while timing their verbal
    responses and monitoring their brain activity

24
  • Results
  • Consciousness of sensations lags behind the
    stimuli by about half a second (500 ms)
  • But the timing of consciousness of the
  • sensations is referred backward to the
  • time of the stimulus
  • Conclusion
  • Fast movements, such as in playing tennis
  • or playing video games, must be implemented
  • unconsciously, and become conscious only
  • about half a second afterwards.

25
Set Two Unconscious Initiation of Voluntary
Actions
  • Set up
  • Subjects fitted with electrodes on their scalps
    attached to an electroencephalogram (EEG) to
    measure their brain activity.
  • An oscilloscope was set up -- a specially
    designed clock with a spot of light revolving
    around the face approximately 25 times per second.

26
Subjects then asked to make small movements with
their hands, e.g. flick their wrists,
spontaneously, when they feel the urge (in
other words, to make a small, voluntary movement
of their own free will) At the same time,
subjects were instructed to watch the
oscilloscope and report the exact position of
the revolving circle at the moment when they
first decide to flick their wrists (in other
words, to record the exact timing of their free
decision).
27
  • Results
  • Subjects reported deciding to make a movement
    approximately 200 milliseconds (ms) prior to
    actual movements.
  • However, the EEG recorded electrical charges in
    the brain building up to the time of the
    movements, which started around 500 ms (up to
    2000 ms) before the movement. He called these
    electrical charges readiness potentials (RPs).
  • In other words, the brain apparently began
    preparing for a movement 300 ms before subjects
    had the conscious impulse to move.

28
  • Conclusion
  • Conscious decisions are preceded by unconscious
    processes in the brain by about a third of a
    second.
  • In other words, decisions are not made
    consciously. Decisions are made unconsciously and
    then become conscious.
  • Conscious initiation of decisions in an illusion.
  • Note
  • Libets results and interpretation of data are
    very controversial, because of the difficulty of
    timing intentions.
  • But
  • Libets results are replicable other people have
    had the same results.
  • Libets results support Jackendoffs and Wegners
    theories.

29
Readings for next week
  • Required
  • Libet, Benjamin (1999) Do we have free will?,
    Journal of Consciousness Studies, Volume 6,
    Numbers 8-9, pp. 47-57(11), available at
    http//pacherie.free.fr/COURS/MSC/Libet-JCS1999.pd
    f
  • Optional
  • Velmans, Max (2002) Preconscious free will,
    Journal of Consciousness Studies 10, 42-61,
    available at
  • http//cogprints.org/3382/1/Cogprints_PRECONSCIOU
    S_FREE_WILL.htm
  • Searle, John (2000), Consciousness, Free Action
    and the Brain, Journal of Consciousness Studies
    7, Vol. 10, No. 10 (October) (on reserve in the
    Philosophy Office)
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