Shamanism, a cross-cultural practice, reflects an innate capacity for altered states of consciousness (ASCs) that can be triggered by stress, sought in rituals, and resemble psychotic experiences. While shamanic sickness, animal transformation, and death-rebirth experiences parallel psychotic symptoms, the key difference is that psychotic experiences worsen under uncontrollable circumstances, whereas shamanic sickness improves through ritualized, controlled engagement with ASCs. When culturally accepted, shamanic vocation does not lead to deterioration but enhances functional capacity as a healer and guide. Shamanic training methods may inform strategies for promoting mental well-being.
The San trance dance, a shamanic ritual, produces altered states of consciousness through specific brain mechanisms. Physical exertion activates the sympathetic nervous system and releases noradrenaline, creating a feeling of rising energy called !num. Hyperventilation activates the amygdala and insula, causing fear and an underwater sensation. During trance, insula changes disrupt the right temporal parietal junction, blurring self/other distinctions and producing body distortion and flight experiences. Altered face and body perception integrates with social information in the anterior temporal lobes, generating human, animal, and theriomorphic figures. Persistent hunting focus enables San men to undergo trance and makes the Eland central to trance imagery in San rock art.