Distilling the neurophenomenological signatures of pure awareness during Transcendental Meditation

A neurophenomenological study using EEG and experience tracing in 33 experienced Transcendental Meditation (TM) practitioners and matched controls (doing mental counting) found that TM reliably elicits reports of pure awareness—a minimal form of experience with little mental content. TM practitioners reported greater intensity and more variable timing of pure awareness, independent of years of practice. Distinct neural signatures separated TM from counting: temporal entropy and aperiodic brain activity best distinguished the two states, while phase-based connectivity was least informative. Comparing TM to its own baseline, low-frequency connectivity dominated and temporal entropy mattered little. These patterns were distributed across the brain, not localized. Counting, but not TM, showed lingering effects after the task. The results characterize pure awareness electrophysiologically and support neurophenomenology as a way to study minimal experience.

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 (EEG) 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 EEG 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.