Flicker adaptation can be explained by probability summation between ON- and OFF-mechanisms

This study considered whether the dynamics of flicker adaptation can be explained in terms of probability summation over time between independent ON- and OFF-processors. Foveal thresholds were measured for flickering probes, and for static ON- and OFF-probes that have durations consistent with the flicker duty cycle. Thresholds were obtained using a probe-flash stimulus onset asynchrony paradigm. The outcome of the experiment suggests that flicker thresholds are lower than the component ON- and OFF-thresholds, and that the flicker response can be predicted by assuming probability summation between the ON- and OFF-mechanisms.