Is All Thinking Unconscious?

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Is All Thinking Unconscious?
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• 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, supporting theories
  of unconscious thinking, e.g. by Jackendoff
  and Wegner.

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Libets Experiments

• Set One
• Backward Referral of Sensations
• Setup
• 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

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• 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.

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Set Two Unconscious Initiation of Voluntary
Actions

• Setup
• 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.

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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).
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• 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.

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• 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.

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• But
• Libets results are replicable other people have
  had the same results.
• Libets results support Jackendoffs and Wegners
  theories (discussed below).
• fMRI
• Chun Siong Soon, Marcel Brass, Hans-Jochen
  Heinze, John-Dylan Haynes Unconscious
  determinants of free decisions in the human
  brain.http//www.nature.com/neuro/journal/v11/n5
  /abs/nn.2112.html

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Jackendoffs Theory

• Ray Jackendoff
• Cognitive Scientist
• Tufts University (with Daniel Dennett)
• Intermediate Level Theory of
• Mental Representation
• Consciousness and the Computational Mind
  (1987)See also http//books.google.com/books?id
  XgHFPVhaeVEC
• Thinking is an unconscious process.

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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

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• 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
  relationshipsare understood, and music is
  understood
• Completely inaccessible to awareness

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• 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.

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The Intermediate-Level Theory of Mental
Representations
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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(or visual form, etc.), 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.

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Why does Jackendoff believe this?

• Thoughts are unconscious, then translated to
  imagery.
• 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

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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).

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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.

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Illusions of conscious will

• Three ways in which the experience of conscious
  willcan 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

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• 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

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• 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

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• 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

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Grailog for 1) P believes that P has not caused
an action A, and P has caused the action A.
cause
believe
A
P
P
cause
negation
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• 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.

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Grailog for 2) P believes that P has caused an
action A, and P has not caused the action A.
cause
believe
A
P
P
cause
negation
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• 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 reason 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(cf.
  rationalization).
• Occurs in cases of hypnosis and direct brain
  stimulation, and in split brain patients.
• Maybe occurs in normal people all the time.

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Grailog for 3) P believes that P has caused an
action A, and P has caused the action A. P
believes that Ps causation of A has reason
X, and Ps causation of A has different reason Y.
cause
unequal
believe
A
P
P
cause
believe
reason
reason
X
Y
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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.

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• 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).

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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.
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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.

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How the illusion is generated
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Readings for next week

• Focus
• Libet, Benjamin (1999) Do we have free will?,
  Journal of Consciousness Studies, Volume 6,
  Numbers 8-9, pp. 47-57(11). http//pacherie.free.f
  r/COURS/MSC/Libet-JCS1999.pdf
• Extra
• Velmans, Max (2002) Preconscious free will,
  Journal of Consciousness Studies 10, 42-61.
• 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)Abstract
  http//www.imprint.co.uk/jcs_7_10.htmlJohn