Lighting, spirituality, and the brain: an EEG-based study of environmental experience in sacred architecture

This study investigated the effects of lighting intensity on users’ relaxation and spiritual experience in religious spaces using electroencephalography (EEG). Nine lighting intensity levels were simulated in the interior of Goharshad Mosque, Iran, while EEG responses from 22 Muslim participants were recorded during exposure through virtual reality. Alpha-band activity and the theta-to-beta ratio were analyzed as neurophysiological indicators. Moderate lighting (250–260 lux) produced the highest alpha activity and the lowest theta-to-beta ratio, indicating optimal relaxation and spiritual experience. These findings support evidence-based lighting design for religious architecture.