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					The Strange Workings of
       the Brain
                    Outline
   Phobias
   Phantom Limbs
   Prosopagnosia and the Capgras Delusion
   Synesthesia
   Memory
   Consciousness
              Phobias



http://www.youtube.com/watch?v=ta-FGE7QELQ
                Phantom Limbs
• Sensation that missing limb is still present
• Often painful
• Can sometimes be controlled, sometimes act on
  their own accord
• Not necessarily the same as missing limb
  – Missing arm felt “6 inches too short”
• Related to mapping of body onto brain
• Mirror treatment
Cortical Homonculus
                Phantom Limbs
• Sensation that missing limb is still present
• Often painful
• Can sometimes be controlled, sometimes act on
  their own accord
• Not necessarily the same as missing limb
  – Missing arm felt “6 inches too short”
• Related to mapping of body onto brain
• Mirror treatment provides visual feedback
Mirror Box Treatment
  Prosopagnosia and the Capgras
            Delusion
• Prosopagnosia: inability to recognize faces
  – Can follow from traumatic brain injury
     • Usually associated with damage to fusiform gyrus (part of
       temporal lobe)
  – Different forms:
     • Apperceptive: severe, can’t even tell gender of person,
       ‘faces make no sense’
     • Associative: can’t make links between face and person
  – Subject may have emotional response without
    conscious recognition
  Prosopagnosia and the Capgras
            Delusion
• Capgras Delusion: person holds a delusion that
  a friend, spouse, parent, etc. has been replaced
  by an identical-looking impostor
• Thought to be like reverse of Prosopagnosia
  – Conscious ability to recognize faces, but without
    automatic emotional response
• Can be caused by traumatic brain injury
  – Possibly due to disconnection between temporal
    cortex (facial recognition) and limbic system
    (emotions)
   Neurological condition in which stimulation in
    one cognitive pathway causes stimulation in
    another


   Examples:
       Symbol --> color or spatial location
       Sound --> color
       Symbol --> personality
   “T’s are generally crabbed, ungenerous
    creatures. U is a soulless sort of thing. 4 is
    honest, but… 3 I cannot trust… 9 is dark, a
    gentleman, tall and graceful, but politic under
    his suavity”
   Can test for synesthia
       1 in 23 people have mild synesthesia
   Likely due to cross activation of different brain
    regions
Testing for Synesthesia
   “T’s are generally crabbed, ungenerous
    creatures. U is a soulless sort of thing. 4 is
    honest, but… 3 I cannot trust… 9 is dark, a
    gentleman, tall and graceful, but politic under
    his suavity”
   Can test for synesthia
       1 in 23 people have mild synesthesia
   Likely due to cross activation of different brain
    regions
   Synesthesia can be beneficial to those effected
       Can aid memory – we’ll see this in a bit
       Many artists have synesthesia
   Synesthetes are truly gods among men
       Famous Synesthetes include: John Mayer, Pharell
        and Eddie Van Halen!!!
   Some think that synesthesia can be related to
    the development of language
       Kiki or Booba?
                           Memory
• Impressive capacities for memory:
  – Solomon Shereshevsky
    • Russian dude active in the early 20th c.
    • Could reproduce incredibly long lists of sounds, words,
      formulas, etc. without error after indefinite amounts of time
    • Diagnosed with 5-fold synesthesia
       – Music  color, touch  taste, etc.
    • Would memorize things by placing them in imaginary
      landscape
       – Might forget something if he couldn’t find it in this landscape
                     Memory
• Impressive capacities for memory:
  – Shass Pollak: Jewish mnemonists who memorized
    more than 5,000 pages of 12 books of Babylonian
    Talmud
  – A pin would be placed on a word, let us say, the
    fourth word in line eight; the memory sharp would
    then be asked what word is in the same spot on
    page thirty-eight or fifty or any other page; the pin
    would be pressed through the volume until it
    reached page thirty eight or page fifty or any other
    page designated; the memory sharp would then
    mention the word and it was found invariably correct.
                        Memory Disorders
•   Henry Gustav Molaison (H.M.)
     – Anterograde amnesia: can’t form new memories
     – Bad epilepsy  brain surgery, removed parts of medial temporal lobes
     – Lost ability to form new long term memories
     – Could still learn new motor memories, but wouldn’t remember having learned them
•   K.C.
     – Intact semantic memory, no episodic memory
     – “unable to describe an event that took place in school that specifically included him;
       however, he knows that he went to school, and he retains the knowledge that he gained
       there“
•   Clive Wearing
     – Memento syndrome as result of Herpes simplex
     – ‘Waking up’ every 20 seconds
     – 8:31 AM: Now I am really, completely awake.
       9:06 AM: Now I am perfectly, overwhelmingly awake.
       9:34 AM: Now I am superlatively, actually awake.
                Consciousness
• Physical theory for consciousness
  – Some argue that consciousness must be a quantum
    phenomenon
• Orchestrated Object Reduction (Orch-OR)
  – Formulated by Roger Penrose and an
    anesthesiologist
  – Godel’s theorem  brain can go beyond
    axioms/algorithms
    • Theorem relates to un-provable-ness of theorms
               Consciousness
• More Penrose
  – For non-algorithmic physics, look to quantum theory
  – Collapse of wave function is probabilistic
  – “states are proposed to be selected by a 'non-
    computable' influence embedded in the fundamental
    level of spacetime geometry at the Planck scale.”
  – Plato: pure values and forms exist in abstract realm
  – Penrose: this realm is the Planck scale
  – Suggests that brain contains these isolated quantum
    systems – possibly in microtubules inside neurons
THE END

				
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posted:8/13/2012
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