The Role of Temporal Factors in Processing Rapid Serial Visual Presentations

Sequentially presented visual stimuli are often employed to investigate the temporal limits of our visual perception and attention. Due to the finite nature of the brains processing capacity, experimental designs attempt to increase temporal separation within series to mitigate potential neural interference between stimuli. This is achieved through shortening of stimulus durations and lengthening of interstimulus intervals. Across two experiments, we parametrically varied these parameters for a serially presented checkerboard wedge stimulus and used inverted encoding modelling to assess the fidelity of the neural representation of spatial location. We found longer interstimulus intervals and shorter stimulus durations produced the most reliable decoding. Varying interstimulus interval altered the fidelity of neural representations via inter-item interference. By contrast, the influence of stimulus duration seemed largely analytic; in a fixed duration block, shorter stimulus duration enabled more presentations, which led to increased decoding accuracy. Distinct anticipatory and reactionary neural events were observed for stimuli presented in triplet sequences, which seemed consistent with forwards and backwards visual masking. The absence of an anticipatory event was observed when backward masking was stronger while a reactionary event was present for every stimulus subjected to forward masking.