Neural, functional, and aesthetic impacts of spatially heterogeneous flicker: a potential role of natural flicker

Spatially heterogeneous flicker, characterized by probabilistic and
locally independent luminance modulations, abounds in nature. It is
generated by flames, water surfaces, rustling leaves, and so on, and it is
pleasant to the senses. It affords spatiotemporal multistability that
allows sensory activation conforming to the biases of the visual system,
thereby generating the perception of spontaneous motion and likely
facilitating the calibration of motion detectors. One may thus hypothesize
that spatially heterogeneous flicker might potentially provide restoring
stimuli to the visual system that engage fluent (requiring minimal
top-down control) and self-calibrating processes. Here, we present some
converging behavioral and electrophysiological evidence consistent with
this idea. Spatially heterogeneous (multistable) flicker (relative to
controls matched in temporal statistics) reduced posterior EEG
(electroencephalography) beta power implicated in long-range neural
interactions that impose top-down influences on sensory processing.
Further, the degree of spatiotemporal multistability, the amount of
posterior beta-power reduction, and the aesthetic responses to flicker
were closely associated. These results are consistent with the idea that
the pleasantness of natural flicker may derive from its spatiotemporal
multistability that affords fluent and self-calibrating visual processing.