When observers view a perceptually bistable stimulus, their perception changes stochastically. Various studies have shown across-observer correlations in the percept durations for different bistable stimuli including Necker cube, binocular rivalry (BR) and bistable moving plaids (MP), which suggests a shared mechanism underlying perception in these paradigms. In this project we explore such shared mechanisms by examining what determines whether a given set of bistable perception paradigms will exhibit correlations in percept durations, and also by examining correlations with other perceptual phenomena that do not directly involve bistability. In our first experiment, we hypothesize that the presence or absence of a certain type of motion can influence whether different bistable paradigms will exhibit correlated percept durations. We found that the correlations between some bistable stimuli are strong, but others are fragile and inconsistent, which prevents us from drawing direct conclusions. In the second experiment, we examine whether between-observer variability in cortical inhibition underlies correlated percept durations between binocular rivalry and bistable moving plaid perception. As a behavioral measure of cortical inhibition, we used center-surround suppression of perceived contrast. While we were able to successfully replicate the correlations between bistable paradigms, there was no correlation between center-surround suppression strength and percept durations for any bistable paradigm. Moreover, the results from a mediation analysis indicate that center-surround suppression is not the mediating factor in the correlation between BR and MP, suggesting that cortical inhibition cannot explain the correlation between various bistable paradigms.
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