Where We Are

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Transcript Where We Are

Where We Are
• Previously -introduction, definitions, ways
of knowing, hard problem, survey of
thought
• Today -methods of neuroscience and
neuronal correlates of consciousness
• To follow -states of consciousness, illusions
and magic, psychotherapy, free will,
music, art and ……
Types of Data
• Third person, objective, measured from
outside, subject to measurement error;
examples temperature, weight, speed,
relative location
• First person, subjective, measured from
within, not verifiable; examples feeling, a
percept, idea
William James
• Empirical study of consciousness should
include introspection and not rely just on
third party observations like behavior
• Find quote from revolution
• Supplanted in 20th century by behaviorism
Behaviorism
• Work of Watson and Skinner
• Man is a machine that is governed classical
conditioning and operant conditioning
• Examples Pavlov’s dog and reward
response
• Materialistic view
Current Methods
• Combine both first and third person
reporting
• Have to agree that there is something to be
like yourself and that is reportable
• Qualia, internally subjective aspect of our
mental lives
Examination of Structure
• Comparative anatomy with animals and
between individuals
• Morphologic changes due to injury
• Phrenology, ethnology (racism)
• Histopathology (microscopic changes)
• Histochemistry (localization of molecules)
Structure
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Angiography
X-Ray
CT scan
Nuclear scan
MRI
Examination of Function
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Physical examination
Intracranial pressure
Electrical activity (EEG)
Direct electrical or magnetic stimulation
Evoked potentials (somatosensory)
PET scans (metabolism)
Function
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fMRI
Direct reading from implanted electrodes
Psychometric testing
Subject reporting (can require specific
training)
fMRI example
• url
http://www.sciencefriday.com/program/arch
ives/200805022
Neuronal Correlates
Consciousness, Crick and Koch
• Look for differences in neuronal states in
different states of consciousness
• Distinguish faciliating and modulating
factors
• Determine minimal differences
• Problem of causality, sufficient and
necessary
Experimental Design
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Gorilla basketball
Necker cubes
Motion blindness
Afterimage effects
Many other
No general agreement
Afterimage Effects
• url Lilac Chaser
• www.michaelbach.de/ot/col_lilacChaser/
index.html
Motion Induced Blindness
• url for Motion induced blindness
http://www.michaelbach.de/ot/mot_mib/index.html
Consciousness Test
• How can we tell whether someone or
something is conscious?
• No third party specific observation
• Materialistic zombie problem(replicate
neuronal mechanism in a machine)
• Turing test for thinking (Hal)
• No Turing test for consciousness
Animal Consciousness
• Analogous EEG findings and thalamocortical connections in mammals
• Mirror self recognition, primates and
dolphins
• Behavioral versatility, mammals create tools
Possible uses of fMRI
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Marker for decision making
Marker for effective advertising
Lie detection and deception
Marker for pain
Marker for drug effect on mood
Marker for anxiety and fear
fMRI in Pain Management
• Biofeedback based on real time self induced
fMRI changes
• url
http://www.ted.com/index.php/talks/christo
pher_decharms_scans_the_brain_in_real_ti
me.html