Fleet DJ, Wagner H, and Heeger DJ, Encoding of Binocular Disparity: Energy Models, Position Shifts and Phase Shifts, Vision Research, 36:1839-1858, 1996.
Abstract: Neurophysiological data supports two models for the disparity selectivity of binocular simple and complex cells in the primary visual cortex. These involve binocular combinations of monocular receptive fields that are shifted in retinal position (the position-shift model) or in phase (the phase-shift model) between the two eyes. This article presents a theoretical analysis of these two models. We describe the quantitative behaviour of these model neurons, along with proposals for how one might measure the relative contributions of phase- and position-shifts towards the disparity selectivity of binocular cells. The analysis also reveals ambiguities in the disparity encoding that is inherent in these model neurons, suggesting a need for a second stage of processing; we propose that pooling the binouclar responses across orientations and scales (spatial frequency) is capable of producing an unambiguous representation of disparity.