Monocular and Binocular Cooperation

Abstract

In this chapter we introduce a model of depth perception that explores one way in which lens accommodation cues can be used to help disambiguate the correspondence problem of stereopsis. Although the model was originally developed to explain how frogs and toads accomplish binocular depth perception without the use of cues from vergence, it is also of general interest as an extension to the class of cooperative stereo models. It consists of two cooperative depth discrimination processes, each acting to build a depth map, with one process receiving monocular depth cues based on accommodation and the other receiving binocular depth cues based on disparity. Mutual excitatory connections between the maps allow the model to converge to a single solution where accuracy is governed by binocularity. The model will also function in a purely monocular mode if binocular input is removed. Neurophysiological data on the visual system of frogs and toads are used to constrain choices made in constructing the model, and results obtained from simulation runs are compared with data from behavioral experiments.