Weaker signals induce more precise temporal-integration

Abstract

It is well known that our perceptual system integrates local information to generate global percepts. Although events in the real world occur over time, it is still unclear how we integrate temporally dispersed information. Here, I systematically explore the relation between the intensity of local signals and the resultant of temporal-integration. Presented sequentially with two directions of variably coherent random dot patterns (40 degrees apart), participants were instructed to report a perceived motion direction by using a mouse driven cursor. As the strength of the motion signal was varied, the behavioral results and qualitative analyses indicate existence of two aspects of temporal-integration, subthreshold integration and suprathreshold integration. In subthreshold integration (when the local signals are subthreshold), stronger signals enhance integration. On the other hand, in suprathreshold integration (when the signals are above threshold), stronger signals decrease integration. As a result, relatively weaker, subthreshold or near threshold signals produce more precise temporal-integration than suprathreshold signals.