Part of Advances in Neural Information Processing Systems 13 (NIPS 2000)
Zhaoping Li, Peter Dayan
Stimulus arrays are inevitably presented at different positions on the retina in visual tasks, even those that nominally require fixation. In par(cid:173) ticular, this applies to many perceptual learning tasks. We show that per(cid:173) ceptual inference or discrimination in the face of positional variance has a structurally different quality from inference about fixed position stimuli, involving a particular, quadratic, non-linearity rather than a purely lin(cid:173) ear discrimination. We show the advantage taking this non-linearity into account has for discrimination, and suggest it as a role for recurrent con(cid:173) nections in area VI, by demonstrating the superior discrimination perfor(cid:173) mance of a recurrent network. We propose that learning the feedforward and recurrent neural connections for these tasks corresponds to the fast and slow components of learning observed in perceptual learning tasks.