Biophysical Model

o Modeling the mammalian visual system

    Studied and gained an intuitive  understanding  of  how the existent
    circuitry is responsible for  establishing  orientation tuning based
    on detailed computer simulations of the early  visual  system in the
    cat, extending from  the  retina  to  the  cortex.   Showed that the
    simulation is in agreementment with experimental data.  Also Studied
    the possible role of the lateral interaction  between cortical cells
    in orientation  selectivity  by  using  a  Hopfield  type of network
    simulation.  The model explained  how  orientation selectivity could
    be sharpened by or arise  from  inhibition  between  cells in visual

  ^{Dong D W and Koch C 1988}
    {Inhibitory model of orientation selectivity}
    {Posted at International Conference on Neural Networks, San Diego}{}

  ^{Wehmeier U, Dong D W, Koch C and Van Essen D 1989}
    {Modeling the mammalian visual system}
    {Methods in Neuronal Modeling: From Synapses to Networks
      Koch C and Segev I (Eds), MIT Press, Cambridge, MA}{ pp 335--360}

o Dynamic temporal decorrelation

    We  investigate  if  well-known  LGN  ion   channel  properties  can
    facilitate  information-theoretic  optimal  coding through  temporal
    decorrelation;  and  if   so,   whether   the   degree  of  temporal
    decorrelation can be adapted dynamically to ensure such optimization
    at longer time scales.  Significant temporal  decorrelation for time
    lags above $50$ ms is achievable in  a  LGN  cell  model with inputs
    generated from  natural  visual  stimuli.   Dynamic decorrelation is
    obtainable  through  adaptive  temporal  filtering  by  varying  the
    resting  membrane  potential.   We  conclude  that  the  biophysical
    properties of LGN cells support the  role  of temporal decorrelation
    and enable a plausible feedback  control  mechanism that dynamically
    adapt to changes in input statistics.

  ^{Truccolo W A and Dong D W: 2001}
    {Dynamic temporal decorrelation: an information-theoretic and
      biophysical model of the functional role of lateral geniculate nucleus}
    {Neurocomputing}{ Vol~38-40, pp~993-1001}

( Papers' Index of Dawei Dong )

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