Abstract
During binocular rivalry perceptual states change across time. Little is known about the dynamics of perceptual changes between and within perceptual states. Recently, we developed a novel tool to track perceptual changes at high spatial and temporal resolution using the InFoRM:Rivalry method(Skerswetat & Bex, 2021). Here, we apply eye tracking analyses to investigate perceptual state changes during rivalry. Sinusoidal gratings (±45°, 2c/°, 2° circular window) were either physically blended to simulate continuous rivalry-states or presented dichoptically to generate perceptual rivalry while leaving participants condition-blinded. 8 trials of low, high, and mixed contrast conditions were deployed. 28 adults moved a joystick to report stimulus appearance in three physical and one rivalry phases. Dynamics of joystick reports (60Hz, 3600 data/trial) were analyzed to classify 6 states (exclusive OS and OD, piecemeal, equal, left-predominance and right-predominance superimposition) and monitor continuous perceptual experiences. Joystick positioning and movements were converted to stable experiences, rivalry “-fixations”, “-tremors”, “-microsaccades”, and “-saccades” using each trial’s mean and standard deviation as boundary criteria. Fast-Fourier-Transform(FFT) was then used to calculate the distribution of perceptual dynamics with Gamma function fits. Across trials, conditions, and participants, medians of relative proportions for stable experiences, rivalry-tremors, -microsaccades, and -saccades were 71.2, 9.7, 7.9,12.1% ± 2.0,1.2, 0.4, 1.0 standard errors, respectively. Gamma fits for each FFT across trials, conditions, and participants showed a median scale of 0.8Hz and R2 of 0.29. AUC varied significantly across contrasts(1-way-ANOVA) and was greatest for the high-contrast condition. The dynamics of rivalry changes provide new insights into the nature of changes between perceptual states, within mixed states, and may be useful for studying atypical neurological phenotypes, such as autism.