Convergence and divergence in a neural architecture for recognition and memory.

How does the brain represent external reality so that it can be perceived in the form of mental images? How are the representations stored in memory so that an approximation of their original content can be re-experienced during recall? A framework introduced in the late 1980s proposed that mental images arise from neural activity in early sensory cortices both during perception and recall. Neurons in the association cortices, by contrast, would not code explicit mental content; rather, they would hold the records needed to reconstruct an approximation of the original perceptual maps in early cortices. Several neurophysiological and neuroimaging studies now lend growing support to this proposal.