Distilling the neurophenomenological signatures of pure awareness during Transcendental Meditation

In contemplative traditions, pure awareness (PA) is described as a wakeful state largely devoid of cognitive content, often considered a case of minimal phenomenal experience (MPE). Transcendental Meditation (TM) provides an excellent empirical model for PA because it is standardized, effortless, and reliably induces reports of awareness with minimal content. We combined electroencephalography (EEG) with phenomenological reports to study PA in 33 experienced TM practitioners and matched controls (performing mental counting). TM practitioners reported greater intensity and variability of PA than controls, regardless of years of meditation practice, consistent with the notion of "automatic self-transcendence". Using multivariate classification analyses of theoretically motivated EEG markers, we revealed a double dissociation in neural signatures. When contrasting TM with controls, temporal entropy and aperiodic dynamics were the strongest discriminators, while functional connectivity based on phase coherence contributed the least. In contrast, when TM was compared with its own baseline, low-frequency functional connectivity dominated, while temporal entropy contributed minimally to classification. This dissociation suggests that PA is characterized by a distinct EEG pattern of signal's entropy and aperiodic neural dynamics compared to ordinary cognition, yet stabilized by slow-frequency oscillatory synchronization relative to rest. Finally, TM showed little evidence of carryover effects from meditation into subsequent rest, whereas controls showed residual changes induced by counting. Together, these results provide the most systematic electrophysiological characterization of PA to date and establish neurophenomenology as a robust framework for advancing the neuroscience of minimal phenomenal experience.