MEG

Waqar Husain et al. (2026) · Brain and behavior

This systematic review of 105 studies examined how religious and spiritual practices -- meditation, prayer, chanting, ritual, and mystical experience -- show up in brain scans. It pooled evidence across eight traditions (Buddhism, Christianity, Islam, Hinduism, Santo Daime, Spiritism, Sant Mat, and mixed traditions) and seven brain-imaging methods, filling a gap left by earlier reviews that each covered only one practice or one faith. Neurotheology, the scientific study of how spiritual experience relates to brain function, asks whether these ancient practices leave a measurable, functional signature on the nervous system. Researchers searched three major databases from their earliest records through mid-2026 and found 450 candidate studies; after removing duplicates and screening for eligibility, 105 studies remained. Each had to study real human participants using an objective brain-measurement tool -- functional or structural MRI, EEG, MEG, PET, SPECT, or similar -- during an actual religious, spiritual, or contemplative practice, not passive exposure to religious words or images. Because the studies varied enormously in tradition, practice, and method, the team combined findings narratively rather than statistically averaging them. Meditation studies (the largest group, 35 studies) consistently found quieter activity in the brain's default mode network, the circuit active during mind-wandering and self-focused thought, alongside more efficient attention-related brain activity in long-term practitioners. Prayer (21 studies) activated brain regions used for understanding other people's minds when prayer was personal and improvised, suggesting the brain treats sincere prayer like a real conversation, and activated reward circuitry during peak spiritual feelings among some worshippers. Chanting and recitation (25 studies) calmed emotional brain circuits -- OM chanting, for example, reduced activity along the same pathway targeted by an approved medical nerve-stimulation therapy. Mental-health-relevant findings (14 studies) included a randomized trial in which loving-kindness meditation eased depression symptoms in diagnosed patients, and a mindfulness program that lowered stress-hormone levels months later. Eleven studies of unusual states -- near-death imagery, ayahuasca ceremonies, and trance -- showed the most widespread brain-network changes of any practice type. The review's authors state plainly that religious and spiritual practices are neurologically real, measurable behaviors, not just subjective reports, and that the brain circuits they engage overlap with those disrupted in depression, anxiety, and addiction. They stop short of claiming these practices treat any diagnosed condition, since most studies involved healthy volunteers rather than patients. The search covered only English-language, peer-reviewed studies, and the wide variety of traditions and methods meant the team could describe patterns but not calculate a single combined effect size.