Experienced meditators show greater forward traveling cortical alpha wave strengths.

Mindfulness meditation involves training attention, commonly toward sensory experiences, with nonjudgmental awareness. Theoretical perspectives propose that meditation increases the precision of sensory processing and reduces the generation/elaboration of top-down expectations. Research suggests forward traveling cortical alpha waves may reflect bottom-up inhibition to enhance signal-to-noise ratios of sensory processing, while backward traveling alpha waves may reflect top-down inhibition based on expectations. We used electroencephalography to test whether the strength of forward and backward traveling cortical alpha waves differed between meditators and a matched sample of nonmeditators during eyes-closed resting (N = 97) and during a visual cognitive (Go/No-go) task (N = 126). Our results showed meditators produced stronger forward traveling waves compared to nonmeditators while resting with their eyes closed and during task performance. Meditators also exhibited weaker backward traveling waves while resting with their eyes closed. These results may indicate a neural mechanism underpinning enhanced attention associated with meditation, as well as a potential neural marker of reductions in mind-wandering, suggested to be associated with meditation. The results also support models of brain function that suggest attention modification is achievable through mental training to increase sensory awareness, which might be indexed by the greater strength of forward traveling cortical waves.