Dynamic variations in the amplitude of low-frequency fluctuations during resting states with the eyes open and closed in the human brain.

Accumulating evidence indicates distinct differences in static brain activity between eyes-open (EO) and eyes-closed (EC) resting states. However, whether dynamic alterations in intrinsic brain activity are significantly associated with ocular states remains unsubstantiated. This study aimed to investigate state-dependent modulations of dynamic intrinsic brain activity across EO and EC conditions through dynamic amplitude of low-frequency fluctuation (dALFF) - a methodological framework integrating conventional amplitude of low-frequency fluctuation metrics with sliding-window analytical approaches. A cohort of 26 subjects (13 males and 13 females) was demographically matched by age, sex, and educational attainment. The dALFF values across brain regions were calculated for both EO and EC states using sliding-window analysis, with subsequent comparison of dynamic brain activity between these ocular conditions. Relative to the EC condition, the EO state exhibited reduced dALFF values in the left Parietal Inf. Conversely, elevated dALFF values were observed in the left Cerebellum 6, left Fusiform, the left and right Occipital Mid, and right Precentral during EO compared to EC. Our principal findings revealed significantly heightened neural activity in the left Cerebellum 6, left Fusiform, the left and right Occipital Mid, and right Precentral during EO compared to EC resting states. Conversely, diminished dALFF was identified in the left Parietal Inf under EO conditions. These differential activation patterns collectively suggest that intrinsic brain dynamics are substantially modulated by visuomotor state transitions, particularly involving ocular status alterations.