Abstract
We introduce a neurobiologically plausible
model of contour integration from visual
inputs of individual oriented edges. The
model is composed of interacting excitatory
neurons and inhibitory interneurons, receives visual inputs via oriented receptive
fields (RFs) like those in VI. The RF centers
are distributed in space. At each location, a finite number of cells tuned to orientations
spanning 180 O compose a model hypercolumn. Cortical interactions modify
neural activities produced by visual inputs,
selectively amplifying activities for edge
elements belonging to smooth input contours. Elements within one contour
produce synchronized neural activities.
We show analytically and empirically that
contour enhancement and neural synchrony
increase with contour length, smoothness
and closure, as observed experimentally.
This model gives testable predictions, and
in addition, introduces a feedback mechanism allowing higher visual centers
to enhance, suppress, and segment contours.
