While many models of the dynamics and interactions of single neurons a
re extant, analogous constructs which attempt to describe large-scale
(greater than or equal to O(10(8))) neuronal activity are few and far
between. Optical imaging of the visual cortex makes such macroscopic n
euronal activity accessible. Symmetries latent in the cortical archite
cture are used here to develop a scheme for analyzing such images. Ln
this way, intrinsic modes of cortical response can be uncovered, using
minimal assumptions. Some of these modes correspond to already-famili
ar features of the functional architecture, and it is highly likely th
at others hold physiological relevance as well. Finally, the number of
such modes that would be required in a more fully developed model (in
corporating cortical dynamics) is approximated.