Depth Perception With Interocular Blur Differences Based on a Spiking Network

Abstract

Visual depth perception is the basic function of the visual nervous system. To a stimulus in the stereo space, the visual nervous system could generate a perception about depth of its position. Experimental observations have demonstrated that interocular blur differences could lead to illusory perceptions about depths of moving stimuli. However, to stimuli with interocular blur differences, influences of different factors on illusory depth perceptions are still unclear. To explore these influences, this paper constructs a plastic two-layer k-winner-take-all (k-WTA) spiking network, simulating primary visual cortical responses. With incompatible stimuli presented into two eyes in experiments, binocular rivalry could occur in the primary visual cortex and interact with depth perception. To simulate binocular rivalry, the network consists of two parallel visual channels driven by left-eye and right-eye stimuli and competing with each other through mutual inhibition. In simulations, the horizontally moving stimulus is filtered with different Gaussian filters to generate paired monocular stimuli with interocular blur differences. The blurry strength, the moving direction and the moving speed perform as varying factors of moving stimuli. The network updates its dynamics through probabilistic inference, reflecting impacts of each factor on both neural responses and binocular rivalry. The modified responses could simulate illusory depth perceptions of stimuli as observed in experiments. To stimuli with interocular blur differences, varying factors could modify binocular rivalry in the network, inducing distinguishing illusory depth perceptions. Based on probabilistic inference, our model could provide possible explanations to illusory depth perceptions with interocular blur differences.