Distilling the Neurophenomenological Signatures of Pure Awareness during Transcendental Meditation.

Summary

Transcendental meditation (TM) practitioners reported greater intensity and variability of pure awareness (PA) compared to matched controls performing mental counting. In a study involving 33 participants, distinct neurophysiological markers were identified that differentiate TM from counting, with temporal entropy and aperiodic dynamics being key discriminators. Additionally, TM showed minimal carryover effects into subsequent rest periods, while counting led to more lasting changes. These findings enhance the understanding of PA through an electrophysiological lens.

Study at a glance

Abstract

Pure awareness (PA) has been proposed as a form of minimal phenomenal experience, but its neurophenomenological signatures remain poorly characterized. Transcendental meditation (TM) offers a particularly tractable empirical model of PA because its procedure is standardized, its induction is effortless, and it reliably elicits reports of awareness with minimal content. We combined electroencephalography with temporal experience tracing in 33 experienced TM practitioners and their matched controls (performing mental counting). TM practitioners reported significantly greater intensity and temporal variability of PA, independent of years of meditation practice. We then used multivariate classification of theoretically motivated electroencephalography markers spanning temporal entropy, aperiodic activity, complexity, and linear and nonlinear functional connectivity. We observed a double dissociation. When TM was contrasted with counting, temporal entropy and aperiodic dynamics were the strongest discriminators, whereas phase-coherence functional connectivity contributed least. Conversely, when TM was contrasted with its own baseline, low-frequency functional connectivity dominated, whereas temporal entropy contributed minimally. Complementary topographical analyses indicated that these differences were not reducible to a few localized univariate effects, but were better understood as distributed multivariate neural patterns. Finally, TM showed little evidence of carryover into subsequent rest, whereas counting induced more residual change. Together, these findings provide a systematic electrophysiological characterization of PA and support neurophenomenology as a tractable framework for studying minimal phenomenal experience.