Abstract
Recently, several studies proposed a probabilistic framework for explaining the phenomenon of binocular rivalry, as an alternative to the classic bottom-up or eye-dominant interpretation of it. According to the new framework, perception is generated from the observer’s internal model of the visual world, based on sampling-based probabilistic representations and computations in the cortex. To test the validity of this proposal, we trained participants with four patterns of non-rival Gabor patches corresponding to four percepts in binocular rivalry settings where the diagonally oriented Gabor patches where presented at two locations. The probability distribution of the appearance of the trained patterns was set as 10%, 40%, 15% and 35% for the four percepts. We tested participants’ prior and posterior distributions of these four perceptions in both binocular rivalry and non-rivalry situations, where they either made judgments by what was perceived in rivalry or guessed what could possibly be the answers of Gabor orientation pairs when they saw only non-rivalry Gaussian noise. Kullback–Leibler divergence and resampling methods were used to compare the pre-training and post-training distributions from each individual participant. For the non-rivalry inference, three out of five participants showed significant difference between pre and post-training distributions of the four possible answers. Compared with the pre, the post-training distribution all shifted towards the target distribution manipulated in the training session in these participants. The initial dominance in binocular rivalry revealed learning effect for the same participants who learned the target distribution from non-rivalry training. In contrast, for binocular rivalry, none of the participants showed change in the distribution of four perceptions overall from pretest to posttest, suggesting no learning effect transferred from non-rivalry training. These results provided no decisive evidence that binocular rivalry is a visual process based on probabilistic representation, but suggested that the onset and subsequent periods of binocular rivalry might need to be distinguished and might result from different mechanisms.