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Relations to biological vision.

Interestingly, the results of this computationally motivated analysis are in qualitative agreement with the results of biological evolution. Neurophysiological studies by Young [] have shown that there are receptive field profiles in the mammalian retina and visual cortex, which can be well modelled by superpositions of Gaussian derivatives.

  
Figure 4: Gaussian derivative kernels up to order four the two-dimensional case.