During binocular rivalry, when each eye sees a different image, perception alternates unpredictably between them. Models propose that neural signals for each image change gradually until reaching a threshold that triggers a switch, but direct evidence was lacking. Measuring steady-state visual evoked potentials (SSVEPs) via EEG in 84 human participants (62 females, 22 males) viewing orthogonal gratings flickering at different frequencies, the amplitude of the suppressed stimulus's signal increased and the dominant stimulus's signal decreased throughout each percept. Longer percepts corresponded to more gradual changes in these signals. The findings match a model where perceptual transitions arise from accumulating noisy signals, providing the first physiological evidence for such threshold-crossing dynamics in human visual cortex.
Training in mindfulness-based stress reduction (MBSR) improves brain-computer interface (BCI) performance by reducing mind wandering and enhancing self-awareness. In a longitudinal intervention study, participants who completed MBSR showed significantly better BCI control compared to controls. This improvement was accompanied by increased frontolimbic alpha activity (9-15 Hz) and decreased alpha connectivity among the limbic network, frontoparietal network, and default-mode network. The changes in frontolimbic alpha activity correlated positively with meditation experience duration and the extent of BCI performance improvement. The findings suggest that mindfulness enables participants to modulate frontolimbic alpha power, thereby improving sensorimotor rhythm-based BCI control.