Title: Is All Thinking Unconscious?
1Is All Thinking Unconscious?
2Jackendoffs 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.
3Three 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.
6The Intermediate-Level Theory of Mental
Representations
7Summary 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.
8Why 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
9Reasons 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).
10Wegners 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.
11Illusions 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.
17Is 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).
19Conscious 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.
20The 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.
21How 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.
23Libets 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.
25Set 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.
29Readings 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)