Vector Symbolic Architectures: Constructions in the Brain

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Vector Symbolic Architectures Constructions in
the Brain

• Simon D. Levy
• Washington Lee University
• Lexington, Virginia, USA
• Ross Gayler
• Baycorp Advantage Value Solutions /
• LaTrobe University
• Melbourne, Australia

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The Appeal of Connectionism(Rumelhart
McClelland 1986)
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WALKED
WALK
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ROARED
ROAR
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SPOKE
SPEAK
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WENT
GO
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Mary wont give John the time of day.
ignores(mary, john)
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Language Isnt (Just) Association Jackendoffs
Four Challenges for Cognitive Neuroscience
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Challenge I The Binding Problem

?
?
?
?
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Solution? Local Representations
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Local Representations
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Challenge II The Problem of Two
?
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Challenge III The Problem of VariablesChallenge
IV Working Memory vs. Long-Term Memory
ignores(X, Y)
X wont give Y the time of day.
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Vector Symbolic Architectures(Plate 1991
Kanerva 1994 Gayler 1998)
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Binding
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Binding
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Bundling


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Unbinding (query)
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Reduction
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Composition / Recursion
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Variables
X
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Conclusions / Future Work

• VSAs address Jackendoffs first three challenges
• Can be implemented as spiking neurons (Eliasmith
  2004)
• Remaining challenge constructions (long-term
  memory) to map from conceptual structure (working
  memory) to symbol sequences