The Problem - Cognitive Sciences

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The Problem
Section One
Grace Gu and Nancy Diaz
About the Author:
Susan Blackmore
Degree in Psychology and Physiology
from Oxford, and a Ph.D. in
Parapsychology.
She has studied the paranormal, and
now she is involved with the study
of meme (A unit of cultural
information, such as a cultural practice
or idea, that is transmitted verbally or
by repeated action from one mind to
another)
Susan Blackmore had a dramatic outof-body experience that convinced
her that consciousness could leave
the body, and made her determined
to become a Parapsychologist. She
is now skeptical about the
paranormal.
Resides in England with her partner
Adam Hart-Davis and two children.
What is Consciousness?
 “Consciousness poses the most baffling problems in
the science of the mind. There is nothing that we know
more intimately than conscious experience, but there is
nothing that is harder to explain.” -Chalmers
 Consciousness is not synonymous with the “mind.”
This confusion has led to the loss of some of it’s
mysteries.
 Throughout history, mysteries that have plagued
scientists’ minds have dwindled away and we have lost
interest. Inversely, the mind/body problem continues to
grow and capture our interests.
When are you Conscious?
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Are you conscious?
Are you conscious when you use the restroom?
Are you conscious when you drive?
Are you conscious when you sleep?
Or dream?
Consciousness is your own
private experience.
The colors you perceive in your mind are your property.
There is no way to publicly share the same experience.
 Some monist theories
emphasize just the mental and
believe objects are just
perceptions of the individual’s
mind.
 Problems arise as to how two
human beings can agree to a
physical object when the
object is outside their mind.
 Materialist monist theories say
that there is only matter and
everything is just a physical
state.
 However, this takes away from
the thought that humans have
control over their fate and
future.
Other beliefs
 Epiphenomenalism: the idea that mental states
are produced by physical events, but have no
causal role to play.
 Physical events cause mental events but in
turn, mental states don’t have any causal
effects on the physical future.
 But then how can we speak about
consciousness if our conscious thoughts don’t
have any influence over our physical
outcomes?
Panpsychism:
 The view that mind is fundamental
 All matter has associated mental aspects or
properties; however primitive.
 But then is a rock aware?
 How about it’s contributing atoms?
 Why should there be mental and physical
properties to everything?
Cartesian Dualism
 Substance dualism is a widely known theory. The bestknown form is from Rene Descartes.
 Cartesian dualism was founded by the intention of
basing the philosophy only on firm foundations that
were beyond doubt.
 “I think, therefore I am.” Descartes concluded that the
thinking self was immaterial and did not take up space
like the mechanical body.
 This view consisted of two entities – the extended stuff
which bodies are made of and the unextended, thinking
stuff of which minds are made.
 How do they interact?
 Descartes’ solution was through the pineal gland in the
center of the brain.
Fall of Dualism
 Few contemporary scientists and philosophers agree that dualism
works.
 Gilbert Rule argued that when we talk of the mind as an entity that
does things, we are making a mistake. Instead, he saw mental
activities as processes, or as the properties and dispositions of
people.
 “Minds are simply what brains do.” – Minsky
 The mind carries out the functions of the brain.
 The two notable dualists are Sir Karl Popper and
Neurophysiologist Sir John Eccles who give us a modern theory of
dualist interactionism.
 They argue that the critical processes in the synapses of the brain
are so finely poised that they can be influenced by a non-physical,
thinking and feeling self, thus the self really controls the brain.
 This however asks for a miracle.
Try defining
Consciousness
Psychology
 The term psychology popped up in the 18th century to describe the
philosophy of mental life.
 It was towards the 19th century that it became a science.
 William James dismissed the dualist concepts of “mind-stuff.”
 He pointed out that consciousness can be abolished by injury to
the brain, or altered by taking alcohol, opium or other substances.
Certain amounts of brain physiology must be included in
psychology.
 James coined the term “stream of consciousness” to describe the
ever changing flow of thoughts, images and feelings.
 Psychophysics was the study between physical stimuli and
reportable sensations; your outer and inner experiences.
 Ernest Weber and Gustav Fechner studied the relationships
between physical luminance and perceived brightness; weight and
sensations of heaviness; or sound pressure and loudness.
 Hermann von Helmholtz
was a German physicist
and physician.
 German philosopher
Edmund Husserl wanted
to focus on “the things
themselves.”
 Helmholtz made the first
measurement of the
speed of conduction of
nerve signals. Popularly
referred to as the
“velocity of thought.”
 This was based off of
Brentano's idea that
every subjective
experience is an act of
reference.
 Helmholtz proposed the
idea of “unconscious
inferences” based off the
tricks our senses and
visual illusions can make.
 Conscious experiences
are about objects or
events, while physical
objects are not about
anything.
Introspection
 Wilhelm Wundt is often called the father of modern
psychology.
 studied the subjective experience by introspection.
 He wanted to be able to build a psychology based on
studying from the inside.
 Wundt claimed that there are two kinds of “psychical
elements”: the objective elements, or sensations such
as tones, heat or light; and the subjective elements or
simple feelings.
 Every conscious experience depended on a union of
these two.
 Introspection fell out of favor because one person’s
claim to an experience can be quite different form
another person’s experience. There was no
agreement.
Behaviorism
 Behaviorism became popular because this branch
could be measured much more reliably.
 John B. Watson argued that psychology did not need
the methods of introspection and indeed could do
without the concept of consciousness altogether.
 Many of Watson’s ideas are built on the ground works
of Ivan Pavlov, whose works included the study of
reflexes and classical conditioning.
 Skinner’s studies of rats and pigeons shaped the
history of reinforcements.
 These new findings led to a period of abolishing
consciousness. Behaviorism's success led to the
avoidance of “consciousness.”
Cognitive Psychology
 As the popularity of behaviorism was fading, cognitive
psychology came into play.
 However, consciousness was still discarded. It was not
welcome in psychology because of the looseness of
the term.
 In different sentences, consciousness conveyed
completely different things.
 As we have more information from research on mental
imagery, altered states of consciousness such as sleep
and drug-induced states, hypnosis, computer science,
consciousness began creeping back into our
vocabulary.
 Many problems that have plagued us in the past have
been solved either through new inventions or thinking.
 Consciousness is one that remains as much a mystery
as it has throughout history.
Close your eyes and imagine
what it’s like to be…….
A BAT !!!
Remember : You use sound of ultrasound for echolocation, you fly, you
are nocturnal, you live with thousands of other bats and you can hang
upside-down….
But can we ever know what is would really be
like for the bat?
 Question was posed in 1950 by American Philosopher
Thomas Nagel.
 “ Consciousness is what makes the mind-body problem
really intractable”-Nagel
 “ There is something it is like to BE that
organism…something it is like FOR the organism”….
 Hofstadter and Dennett, “ What is it like from the inside?”
 Consciousness = Subjectivity = “ What it is like to be…”
Qualia
 Private qualities. You only experience it, privately,
incapable of being expressed because only you
experience it in your own way.
 A quale is what something is like…our conscious
experience consists of qualia.
 Now the problem becomes : “How are qualia related to
the physical world, or how an objective physical brain
can produce subjective qualia”
Dualist believe that
qualia are part of a
separate mental
world from physical
objects
Idealists
believe that
everything is
ultimately
qualia
Epiphenomenalists believe that qualia exist but have no casual properties
The problem with qualia…
They do not have physical properties that can be
measured
Are qualia something separate from the brain?
Do qualia make any difference?
Does a quale contain information above and beyond the neural
information it depends on?
This is where Mary can help us out……
Mary the Color Scientist
•Lives in far far future, when everything there is
to know about the physical processes in the
brain and how they produce behavior is known.
•Knows absolutely everything about : color
perception, the optics of the eye, the properties
of colored objects in the world, the processing
of color info.in the visual system, etc.
•BUT she has been brought up all her life in a
black and white room, observing the world
through a b/w TV monitor…
•She has never seen any colors at all
• Suddenly she is let out of her black and white
room and sees colors for the first time….
What happens?
Will she just shrug and
say, “That’s red, that’s
green, nothing new of
course”?
Will she gasp with
amazement and say
“Wow-I never realized
red would look like that!”
The Mary Thought
Experiment

Developed by Frank Jackson devised the Mary thought experiment as an
argument against physicalism
SURPRISED:
When Mary sees color, she will obviously learn something fundamentally new –
what red is like.
She now has qualia as well as the physical facts about color
No amount of information could have prepared her for the raw feel of it is like to
see color (Chalmers)
You believe that consciousness,subjective experience, or qualia are something
additional to knowledge of the physical world.

NOT SURPRISED:
Dennett argues that we fail to allow Mary to know everything there is not know
about color.
She already knew what kind of impressions color would induce.
You believe that knowing all the physical facts tells you everything there is to
know– including what it is like to experience something.
The Philosopher’s Zombie
•Someone who looks like you…behaves exactly like you BUT is not
conscious.
•There is nothing it is like to be this creature (No view from
within…no qualia)
•To many thinkers a zombie is easy to imagine and obviously
possible, at least in principle.
•Zombie earth
•Same as us, but are not able to understand conscious terms
in the way we do because they have no conscious
experience(language, thinking, imagining, dreaming,
believing, etc, but could talk of these!)
•Conversations with them would seem natural and normal.
•It would think it was conscious, even if it wasn’t.
•What do you think ???
Is there a hard problem?
How do we find the solution?
1. The hard problem is
insoluble
 The problem of subjectivity is
hopeless – Nagel
 Our human kind of
intelligence is wrongly
designed for understanding
consciousness – British
Philosopher Colin McGinn
 Our own awareness is ‘the
ultimate tease…forever
beyond our conceptual grasp’
– American evolutionary
psychologist Steven Pinker
2. Solve it with drastic
measures
 Rethink all that we know
about the universe
 We can only understand
consciousness when we have
a new theory of information
 Fundamental rethink of he
nature of the universe is a
MUST !
3. Tackle the easy problems
 Tackle the easy problems first
and eventually we’ll pump into
the answer (about attention,
learning, memory or
perception).
 Why? We need to start with
something reasonably
tractable such as visual
binding.
 Those who work on the easy
problems, come close to
arguing that there is no
separate hard problem.
4. There is no hard problem

Ignore the problem…for now
1. Start with the easy problems
2. Solutions to the easy problems
will change our understanding of
the hard problem, so trying to
solve the problem now is
premature
3. A solution to the hard problem
would only be of use if we could
recognize it as such, and for the
moment the problem is not well
enough understood.
Disassociation
 There is a dissociation between fast motor
reactions and conscious perception.
 Experiment with showting “Tah” when subject
saw a light go on showed that there was an
automatic reflex versus consciousness
perception (Castiello).
 Milner and Goodale argue that there is a
distinction based on different functions of the
brain; fast visuomotor control and less urgent
visual perception.
 Much of their evidence is from patients with
brain damage.
No doubt about one thing: We seem to do
some things consciously and others
unconsciously.

Divide actions into five types:
1.
Are always unconscious
i.e. I can wiggle my toes or sing a song, but I cannot consciously grow my hair
2.
Some actions that are normally carried out unconsciously can be brought back under
conscious control by giving feedback of their effects, or “biofeedback”
i.e. We may unconsciously open the door, but we have no idea all the muscle
power it takes to do so. The whole action seems to be done consciously, while the
details remain unconscious.
3.
Many skilled actions are initially learned with much conscious effort
i.e. You probably first learned to ride a bicycle with the utmost conscious
concentration... but the it becomes automatic. Can be counter-productive: get off
your bike and you might find that you cannot even walk normally.
4.
Many such skilled actions, once well learned, can be done either way.
i.e. Classic example: driving a car. Every driver must have had the experience of
arriving at a familiar destination without apparently having been conscious of the
journey. Scary part: potentially life-threatening decisions being made correctly
without, apparently, any conscious awareness.
5.
Some actions seem always to be done consciously
I.e. When we have to make a difficult moral decision, we seem to be far more
conscious than when deciding what clothes to put on. Tempting: To say that
these kinds of thinking or decisions require consciousness.
Functionalism
 View that mental states are functional states.
 I.e. Someone in pain = input from damage done. Other
mental states like the desire for the pain to go away, or
crying = output.
• Most common view: Works well for explaining mental
sates, but cannot deal with phenomenal consciousness.
• Artificial Intelligence: If it can do the same functions as
a conscious system, it would also be conscious.
Global Workspace Theory (GWT)
 By American Psychologist Bernard Baars
 Cognitive system is built on a global workspace or blackboard
architecture, analogous to a stage in the theater of the mind.
 Unconscious processors compete for access to the spotlight of
attention that shines on the stage, from where information is
broadcast globally to the unconscious audience.
 This global broadcast constitutes consciousness.
 Actions that are performed consciously are shaped by conscious
feedback, while unconscious actions are not.
 i.e. Unconsciously make a speech error, but when you consciously
hear the mistake, you can make it right because consciousness creates
global access to further unconscious resources.
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