Transcendent states achieved through meditative practices have been reported across cultures and history, yet few studies have systematically examined them. This systematic review of 25 studies with 672 participants found that transcendent states during meditation are most consistently associated with slowed breathing, respiratory suspension, reduced muscle activity, increased EEG alpha power and coherence, and functional neural connectivity. Participants described the state as relaxed wakefulness in a phenomenologically different space-time. The review included various traditions: Buddhist, Christian, Mixed, and Vedic (Transcendental Meditation and Yoga). Heterogeneity between studies precluded meta-analysis, so conclusions are qualitative and preliminary.
Psychedelic experiences and transcendental experiences during meditation are fundamentally different across five dimensions: EEG patterns (gamma vs alpha), brain blood-flow (decreased vs higher frontal), content of experience (intense mental/emotional vs content-free self-awareness), mechanism of action (influenced by set and setting vs transcending them), and therapeutic application. Therefore, equating the two or using findings from one to justify the other is inaccurate. Both areas merit careful research, but their results should not be superficially combined.