Paper Available: Model of Cortical Layer 4

[Ken Miller]

The following paper is now available as
ftp://ftp.keck.ucsf.edu/pub/ken/kayser_miller.pdf
or from
http://www.keck.ucsf.edu/~ken (click on 'Publications', then on
                               'Models of Neural Development').

Kayser, A.S. and K.D. Miller.  "Opponent inhibition: A developmental
model of layer 4 of the neocortical circuit". 
    This is a final draft of a manuscript that has now appeared as
Neuron 33, 131-142 (2002). 

Summary:

We model the development of the functional circuit of layer 4, the
input-recipient layer, of cat primary visual cortex.  The observed
thalamocortical and intracortical circuitry codevelop under Hebb-like
synaptic plasticity.  Hebbian development yields opponent inhibition:
inhibition evoked by stimuli anticorrelated with those that excite a
cell.  Strong opponent inhibition enables recognition of stimulus
orientation in a manner invariant to stimulus contrast.  These
principles may apply to cortex more generally: Hebb-like plasticity
can guide layer 4 of any piece of cortex to create opposition between
anticorrelated stimulus pairs, and this enables recognition of
specific stimulus patterns in a manner invariant to stimulus
magnitude.  Properties that are invariant across a cortical column are
predicted to be those shared by opponent stimulus pairs; this
contrasts with the common idea that a column represents cells
with similar response properties.



Ken
 
        Kenneth D. Miller               telephone: (415) 476-8217
	Associate Professor		fax: (415) 476-4929
        Dept. of Physiology, UCSF	internet: ken at phy.ucsf.edu
        513 Parnassus			www: http://www.keck.ucsf.edu/~ken
        San Francisco, CA 94143-0444