Fluctuation in the retina: noise-enhanced processing via random sampling and microsaccades?

摘要

The goal of this work is to study the fluctuations the eye is subjected to, from the point of view of noise-enhanced processing. In this paper we consider a basic model of retina: a regular sampler subjected to space and time fluctuations to model the random sampling and the eye-tremor respectively. We also take into account the filtering made by the photoreceptors and we focus on a stochastic model of natural scene. To quantify the effect of the noise, we study the correlation coefficient between the signal acquired by a given photoreceptor, and a given point of the scene the eye is looking at. We then show on academic examples as well as on a more realistic case that the fluctuations which affect the retina can induce noise-enhanced processing effects. Finally, we interpret why this effect is possible. We especially interpret the microsaccadic movement of the retina as a stochastic control.