Heleen A Slagter¹ (h.a.slagter@vu.nl), Surya Selvam², Brendan T Hutchinson³, Daphne Witmer⁴, Tess Roder⁵, Johannes J Fahrenfort⁶, Ruben E Laukkonen⁷; ¹Vrije Universiteit Amsterdam

Predictive processing theories propose that perceptual experience is strongly shaped by prior beliefs. Some priors are particularly resistant to change, as illustrated by bistable phenomena such as binocular rivalry—where distinct stimuli presented to each eye produce alternating percepts rather than a stable mixed image. Contemplative traditions suggest that meditation can attenuate the influence of such priors, potentially expanding the scope of conscious perception. In this study, we examined whether volitional control over rivalry is possible via meditation-induced attention modulation. Advanced meditators (n=26) viewed flickering rivalry stimuli under three conditions: focused attention (FA), open monitoring (OM) and a no-meditation control. Each condition included self-report, no-report, and localizer blocks. We hypothesized that FA, by stabilizing attention on the current percept, would prolong individual percept durations, whereas OM, by fostering non-selective attention to all aspects of experience, would increase mixed percept durations. This, in turn, should reduce self-reported perceptual switches in both meditation conditions, albeit for different reasons. Perceptual switches were quantified using behavioral self-reports and changes in perceptual content were tracked over time by combining two EEG analysis methods: pattern-classification applied to rhythmic entrainment source separated (RESS) time series. As hypothesized, behavioral reports revealed fewer switches in both meditation conditions, with some meditators reporting exceptionally long percept durations (up to 180s). First EEG analyses show high decoding accuracy and strong correspondence between neural and self-reported switches in the no-meditation condition, supporting the feasibility of objective rivalry-tracking. Strikingly, initial EEG-decoding findings confirm exceptionally long percept durations in some meditators. Full sample results will illuminate the extent to which control over conscious perception is possible through meditation.