Distilling the Neurophenomenological Signatures of Pure Awareness during Transcendental Meditation.

Pure awareness, a state of minimal phenomenal experience, can be reliably studied through transcendental meditation. In 33 experienced TM practitioners compared to controls doing mental counting, TM produced significantly greater intensity and temporal variability of pure awareness, unrelated to years of practice. Using EEG and multivariate classification, a double dissociation emerged: temporal entropy and aperiodic dynamics best distinguished TM from counting, while low-frequency functional connectivity best distinguished TM from its own baseline. These differences reflected distributed neural patterns, not localized effects. TM showed little carryover into rest, unlike counting. The findings characterize pure awareness electrophysiologically and support neurophenomenology as a framework for studying 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 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.