Effects of Contrast on the Anticipatory Dynamics of a Retina

The retinal network is a natural computational system with the ability to perform multiple tasks concurrently, including generating anticipatory responses to predictable stimuli. To study the effects of signal contrast on retinal anticipatory responses, experiments are conducted on bullfrog retinas using a multi-electrode array (MEA) system. The method of time lag mutual information (TLMI) between the retinal responses and the stimulation is used to assess the retina’s anticipatory capabilities. Results indicate that higher contrast stimulation generally yields better anticipation and higher information transfer. However, some channels only exhibit anticipatory behavior when the contrast is sufficiently high. This finding implies that performing anticipatory tasks, such as playing badminton, may be more challenging in low-contrast visual environments. The observation of the Weber-Fechner law through TLMI suggests that the amount of information transferred could serve as a measure of our visual perception (sensation) of the external physical world.