Seeing between the Pixels The Mind's Eye When you ponder how
best to represent a picture, a promising approach is to ask how
people or animals see images. What kinds of data structures does
the brain employ for visual information? The input end of the
visual system is clearly a pixel-based device: The retina of the
eye has much in common with the array of photosensors in a
digital camera. Nevertheless, we do not see in pixels. No one
experiences the visual surround as an array of colored dots—not
even Seurat. At the level of conscious awareness, what we see
are faces, trees, trombones, streetlights, paintings—and all of
these objects seem to have a continuous and unpixelated surface,
no matter how closely we look at them. Evidently visual
information is re-encoded somewhere along the neural pathways of
the eye and the brain. A part of the brain where image
representation has been studied extensively is a region known
variously as the primary visual cortex, the striate cortex or
simply V1. In the 1960s David H