A model for separation of spatial and temporal information in the visual system

摘要

The two-dimensional Fourier transform model proposed for signal processing in the visual system is given an analytical formalism and is further augmented to a three-dimensional transform to include time. Yet another generalization incorporates a complementary system of expansion in polar coordinates. It is proposed that cortical cells sensitive to moving gratings are in fact narrow-band spatio-temporal frequency filters. The model proceeds with an integration along the temporal frequency axis, thereby obtaining a “frozen” picture of a dynamic pattern. This gives a new interpretation to the functional significance of the columnar organization of the striate cortex. A treatment of the bandwidth of cortical neurons clarifies the problem of the different bandwidths previously repor