A neurophenomenological framework is proposed for studying non-ordinary states of consciousness (NSCs) such as hypnosis, meditation, and psychedelics. NSCs involve shifts in what appears to the experiencer or how it appears, enabling investigation of the plastic and dynamic nature of experience across mind, brain, body, and context. The approach highlights NSCs as catalysts of transformation in clinical practice by refining understanding of relationships between subjective experience and neural dynamics. Ethical implications for standard conceptions of health and pathology are outlined, along with the crucial role of experience-based know-how in NSC research and application.
In a double-blind, randomized, crossover, placebo-controlled trial with 25 healthy adults, psilocybin (10–20 mg oral) decreased EEG power in slow frequency bands (theta and alpha) and increased power in fast frequency bands (beta, gamma1, gamma2) compared to placebo. Connectivity within the default-mode network and localized parietal network increased under psilocybin. Changes in EEG power and connectivity correlated positively with subjective experiences measured by the Altered States of Consciousness Questionnaire. Baseline EEG features predicted subjective alterations, suggesting that specific brain activity patterns could serve as biomarkers for tailoring psilocybin therapy.