Anatomical and physiological correlates of visual computation from striate to infero-temporal cortex

A review of the calculus of two-dimensional mappings is provided, and it is shown that cortical mappings are in general locally equivalent to the sum of a conformai mapping and a shear mapping. Currently available data suggests that a conformai (isotropie) mapping is sufficient to model the global topography of primate striate cortex, although the addition of a shear component to this mapping is outlined. A similar analysis is applied to the local map structure of striate cortex. Models based on a local reiteration of the complex logarithm and on Radon (and backprojection) mappings are presented. A variety of computational functions associated with the novel architectures for image processing suggested by striate cortex neuroanatomy are discussed. Applications to segmentation, perceptual invariances, shape analysis, and visual data compression are included. Finally, recent experimental results on shape analysis by neurons of infero-temporal cortex are presented.