The Architecture The Architecture of Thoughtof Thought

Ein Prezentazien von David WilliamsEin Prezentazien von David Williams

Old NeuroscienceOld Neuroscience

1861- Paul Broca and the Brain-1861- Paul Broca and the Brain-DamagedDamaged

-Discovered Broca’s Area (Speech -Discovered Broca’s Area (Speech production) by studying aphasics production) by studying aphasics (Also Wernicke’s).(Also Wernicke’s).

1965 – Hubel and Wiesel and 1965 – Hubel and Wiesel and ReorganizationReorganization

Memory Memory Retrieval/Learning.Retrieval/Learning.

Lashley (1Lashley (1stst half of 20 half of 20thth Century) And Century) And the Search for the Engram.the Search for the Engram.

Penfield’s Probing Penfield’s Probing Jacobson’s rats (1965) and transferal Jacobson’s rats (1965) and transferal

of Pavlovian knowledge through of Pavlovian knowledge through RNA.RNA.

Planarians learned to avoid light.Planarians learned to avoid light.

<Chemicals, Connections…><Chemicals, Connections…>

Some TermsSome Terms

Hippocampus – gateway to long-term Hippocampus – gateway to long-term memory (Memento). May work with memory (Memento). May work with spatial knowledge (London Cab Drivers)spatial knowledge (London Cab Drivers)

Amygdala – Emotional memory Amygdala – Emotional memory formation, signals hypothalamus to formation, signals hypothalamus to create hormones, damage impairs create hormones, damage impairs Pavlovian learning.Pavlovian learning.

Glutamate, GABA = Excitatory, Glutamate, GABA = Excitatory, Inhibitory. (Molecules)Inhibitory. (Molecules)

Newer NeuroscienceNewer Neuroscience

Cells, Synapses, Formation.Cells, Synapses, Formation.

From Short Term to Long From Short Term to Long TermTerm

Glutamate and GABAGlutamate and GABA(Early LTP)(Early LTP)

Glutamate – opens cell to positive ions Glutamate – opens cell to positive ions that create potential that moves down that create potential that moves down axon.axon.

GABA – brings in more negative ions.GABA – brings in more negative ions. Glutamate received by AMPA and NMDAGlutamate received by AMPA and NMDA -NMDA unblocked when AMPA stimulated-NMDA unblocked when AMPA stimulated -Extra AMPA receptors (ca 10 minutes)-Extra AMPA receptors (ca 10 minutes)

Other Methods of LTPOther Methods of LTP

Calcium (Positive ions) activates Calcium (Positive ions) activates calpain, collapses nerve cell, exposes calpain, collapses nerve cell, exposes more glutamate receptors.more glutamate receptors.

Calcium => Enzymes => CREB => Calcium => Enzymes => CREB => genes => Proteins synthesizedgenes => Proteins synthesized

Subsequent stimulation sends Subsequent stimulation sends proteins to the stimulated synapsesproteins to the stimulated synapses

Late LTPLate LTP

Synapse SpecificSynapse Specific Relies on Protein Synthesis Relies on Protein Synthesis

-New Glutatmate Receptors-New Glutatmate Receptors

-New Connections-New Connections

-Stronger Existing connections-Stronger Existing connections

-Induced by a series of 3 or more -Induced by a series of 3 or more stimulations around 10 minutes stimulations around 10 minutes apart.apart.

Self-Centered MemoriesSelf-Centered Memories

(Heatherton) Medial Prefrontal Cortex (Heatherton) Medial Prefrontal Cortex = Reflexive X system= Reflexive X system

(Spindle cells, Self-Reflection)(Spindle cells, Self-Reflection)

Hippocampus = Reflective C systemHippocampus = Reflective C system

-Decision to move = Predictions of -Decision to move = Predictions of ResultsResults

-Slight difference = Synaptic rewiring-Slight difference = Synaptic rewiring

-Huge difference = Outside source -Huge difference = Outside source blamed.blamed.

Synaptic PlasticitySynaptic Plasticity

Hebb: “Neurons that Hebb: “Neurons that Fire Together, Wire Fire Together, Wire Together.”Together.”

Alvaro Pascual-Leone Alvaro Pascual-Leone of Harvard and the of Harvard and the Piano Exercise.Piano Exercise.

Merzneich’s Monkeys Merzneich’s Monkeys and the Finger Foodand the Finger Food

Neuroplasticity in Neuroplasticity in ChildrenChildren

Rearrangement after strokeRearrangement after stroke Rearrangement during Rearrangement during

childhood/Formation.childhood/Formation.

-Blind children have their visual cortex -Blind children have their visual cortex reassigned to the somatosensory reassigned to the somatosensory (touch) cortex. (Cross-modal (touch) cortex. (Cross-modal reassignment)reassignment)

Mriganka Sur: Rewiring Induced Mriganka Sur: Rewiring Induced Temporary Synesthesia in Newborn Temporary Synesthesia in Newborn Ferrets.Ferrets.

In Recent News:In Recent News:

Protein Kinase M-Zeta (August ’06)Protein Kinase M-Zeta (August ’06) -Persistently Strengthens Synaptic -Persistently Strengthens Synaptic

ConnectionsConnections -Inhibiting It Erases Memories-Inhibiting It Erases Memories (Treat PTSD, Phantom Limb, (Treat PTSD, Phantom Limb,

Chronic Pain)Chronic Pain) Found to be bound up in Alzheimer’s Found to be bound up in Alzheimer’s

Disease.Disease.

……But the MechanismsBut the Mechanisms

Professor Vincent Walsh of the Professor Vincent Walsh of the Institute of Cognitive Neuroscience Institute of Cognitive Neuroscience at London, Leader of the Visual at London, Leader of the Visual Cognition Research group on the Cognition Research group on the state of the field:state of the field:

We have a good spatial map…what We have a good spatial map…what we lack is a good temporal map. we lack is a good temporal map.

The Brain as a ComputerThe Brain as a Computer

Soups and sparks:Soups and sparks: Glial cells: Thought to Glial cells: Thought to

be support cells, no be support cells, no part in information.part in information.

Only in this decade Only in this decade were they found to were they found to respond to respond to CHEMICAL signals, CHEMICAL signals, not electrical ones.not electrical ones.

ComplexityComplexity

Vision Is Not Just Seeing….Vision Is Not Just Seeing….

-James Thurber and Charles Bonnet -James Thurber and Charles Bonnet SyndromeSyndrome

---Vision’s version of Korsakoff’s ---Vision’s version of Korsakoff’s Syndrome.Syndrome.

-Damage to certain areas create-Damage to certain areas create

--loss of motion sense--loss of motion sense

--loss of facial recognition--loss of facial recognition

--around 30 different areas identified.--around 30 different areas identified.

Spiritual ComputationSpiritual Computation

Newberg, D’AquiliNewberg, D’Aquili Meditation and Orientation by the OAAMeditation and Orientation by the OAA Cutting off sense to the brain leaves no Cutting off sense to the brain leaves no

way to identify “otherness”way to identify “otherness” Part of religious experiencePart of religious experience

Phantom LimbsPhantom Limbs

People with phantom People with phantom limbs generally feel limbs generally feel pain in this limb…pain in this limb…

But Ramachandran But Ramachandran discovered rewiring discovered rewiring that also affected the that also affected the phantom.phantom.

Sensations on the face Sensations on the face felt in the phantom…felt in the phantom… Penfield Homunuclus

ImplicaitonsImplicaitons

Richard Andersen, Joel Burdick, and Richard Andersen, Joel Burdick, and Yu-Chong Tai of CalTech have Yu-Chong Tai of CalTech have worked on direct-to-brain worked on direct-to-brain prostheticsprosthetics

Paul Dario and the Cyberhand Paul Dario and the Cyberhand ProjectProject

QuestionsQuestions

Creative ImpulseCreative Impulse Non-material induces change in Non-material induces change in

materialmaterial Sense of Self, Personal EthicsSense of Self, Personal Ethics

SourcesSources WikipediaWikipedia Synaptic Self, How Our Brains Become Synaptic Self, How Our Brains Become

Who We AreWho We Are, Joseph LeDoux, 2004., Joseph LeDoux, 2004. The Mind and the Brain: Neuroplasticity The Mind and the Brain: Neuroplasticity

and the Power of Mental Forceand the Power of Mental Force, Jeffrey , Jeffrey M. Schwartz and Sharon Begley, 2002.M. Schwartz and Sharon Begley, 2002.

The Singularity is Near: When Humans The Singularity is Near: When Humans Transcend BiologyTranscend Biology, Ray Kurzweil, 2005, Ray Kurzweil, 2005

In the Palaces of MemoryIn the Palaces of Memory, George , George Johnson, 1991.Johnson, 1991.

SourcesSources

Zimmer, Carl. "The Neurobiology of Zimmer, Carl. "The Neurobiology of the Self" the Self" Scientific AmericanScientific American 293.5 293.5 (Nov 2005): 92-98. (Nov 2005): 92-98.

Fields, Douglas R. "Making Fields, Douglas R. "Making Memories Stick" Memories Stick" Scientific AmericanScientific American 292.5 (Feb 2005): 75-81. 292.5 (Feb 2005): 75-81.