Sound-based Meditation Alters Brain Activity: EEG Evidence for Power Reduction and Enhanced Conscious Alertness.

Résumé

BACKGROUND: Meditation is known to modulate neural activity and enhance cognitive and emotional well-being. While previous studies have largely reported increases in alpha and theta activity, the neurophysiological effects of structured sound-based meditation practices remain underexplored.PURPOSE: This study investigated the neurophysiological and subjective effects of rhythmic sound meditation (RSM) compared to a resting state (RS) condition. We aimed to identify EEG spectral patterns and changes in subjective alertness during this meditation protocol.METHODS: Fifteen healthy adults (mean age = 24.8 ± 3.6 years) participated in two 26-minute sessions (RSM and RS) in a randomised, counterbalanced design. EEG data were recorded using a 64-channel actiCHamp system, and power spectral density was analysed across delta, theta, alpha, beta, and gamma bands. Subjective alertness was assessed before and after the sessions using the Stanford Sleepiness Scale (SSS). Statistical analyses were conducted using Yuen's paired -test with FDR correction.RESULTS: RSM reduced EEG power across all frequency bands, particularly in prefrontal and frontocentral regions, compared to RS ( < .05, FDR-corrected). Power reductions were observed across delta, theta, alpha, beta, and gamma bands, with the most pronounced effects in frontal areas. SSS scores showed increased alertness post-RSM (93.3% alert) versus decreased alertness post-RS (73.3% alert).CONCLUSION: RSM induced distinct neurophysiological changes, characterised by widespread EEG power suppression in frontal regions and heightened subjective alertness. These findings support its potential for promoting altered states of consciousness, contributing to the neuroscientific understanding of sound-based meditation.