Understanding the processing of information in our cortex is a significant part of understanding how the brain works and of understanding intelligence itself, arguably one of the greatest problems in science today. In particular, our visual abilities are computationally amazing and we are still far from imitating them with computers. Thus, visual cortex may well be a good proxy for the rest of the cortex and indeed for intelligence itself. But despite enormous progress in the physiology and anatomy of the visual cortex, our understanding of the underlying computations remains fragmentary.
I will briefly review hierarchical feedforward quantitative models of the ventral stream which, heavily constrained by physiology and biophysics, are surprisingly successful in explaining several physiological data and psychophysical results in rapid scene categorization. I will then focus on the limitations of such models for object recognition, suggesting specific questions about the computational role of attention and about recognition tasks beyond scene classification.