Trance designates a broad family of altered states characterised by reduced external awareness, heightened internal focus, and often dissociation from ordinary self-monitoring. Principal varieties include:
Franz Anton Mesmer (1734–1815) proposed in the 1770s that a fluid he called "animal magnetism" could be directed through the body by practitioners to effect healing. Though his theory was discredited by a 1784 Royal Commission chaired by Benjamin Franklin, the phenomena he observed — altered responsiveness, suggestibility, apparent anaesthesia — were real. James Braid, a Scottish surgeon, demonstrated in 1843 that the phenomena were neurological rather than magnetic, coining the term "hypnosis" (from Hypnos, the Greek god of sleep) and establishing it as a legitimate subject of scientific inquiry. Jean-Martin Charcot used hypnosis at the Salpêtrière hospital in Paris in the 1880s as a tool for studying hysteria. Sigmund Freud studied under Charcot and initially used hypnosis extensively before developing free association as his primary therapeutic method.
Milton Erickson (1901–1980) transformed therapeutic hypnosis through his development of indirect suggestion, therapeutic metaphor, and utilisation of trance states tailored to individual subjects. The Stanford Hypnotic Susceptibility Scale, developed by Weitzenhoffer and Hilgard, provided a standardised measure of hypnotic responsiveness and established that susceptibility is normally distributed in the population, with a small fraction of highly hypnotisable subjects constituting a distinct population for research.
Neuroimaging studies of hypnosis show characteristic changes including:
Hypnotic age regression and past-life regression have attracted parapsychological interest. Subjects under hypnosis sometimes produce detailed narrative accounts of previous lives. Investigation has consistently demonstrated that such accounts are susceptible to cryptomnesia (forgotten memories of historical material that is unconsciously elaborated into first-person narrative) and to therapist suggestion. No regression account has provided verifiable information shown to exceed what the subject could have encountered through ordinary channels. Pierre Janet's 1880s work on somnambulism — hypnotic states in which subjects appeared to access normally inaccessible memories and engage in complex behaviour — established that hypnotic dissociation could produce multiple apparent personalities with distinct memory systems, foreshadowing later DID research.
Historian of religion Mircea Eliade provided the foundational comparative study in Shamanism: Archaic Techniques of Ecstasy (1951). Eliade characterised shamanic trance by the concept of the "soul journey" — a voluntary dissociation in which the practitioner's consciousness travels to non-ordinary realms for healing or information retrieval. Neurological parallels have been proposed between shamanic trance (induced by rhythmic drumming at ~4–7 Hz, consistent with theta entrainment), DMT and plant medicine experiences, and near-death phenomenology. Anthropologist Michael Harner's development of "core shamanism" brought shamanic techniques to Western settings, generating a new experimental population.
Advanced meditative states — the jhana states of Theravada Buddhism and the samadhi of yogic traditions — represent a spectrum from focused absorption to objectless awareness. Neuroimaging of long-term meditators during deep practice shows distinctive EEG signatures including high-amplitude gamma synchrony, reduced amygdala reactivity, and altered default mode network dynamics. Contemplative neuroscience has documented stable trait changes in practitioners that persist outside formal meditation, suggesting enduring neuroplastic effects of sustained trance practice.
Ritual trance — Vodou possession ceremonies, Whirling Dervish dhikr, fire walking, ecstatic dance — produces physiologically verified altered states including trance-associated analgesia, reduced pain responses, and autonomic changes. A 1969 meta-analysis by Honorton and Krippner examined psi performance under hypnotic conditions and found a statistically significant advantage for hypnotised subjects in ESP tasks compared to waking controls. The theta EEG predominance shared by hypnotic trance, shamanic drumming, and deep meditative absorption has been proposed as a common neurological substrate for enhanced psi receptivity, though direct experimental evidence for this mechanism remains limited.
This page presents documented research and reported phenomena. No claims about validity or mechanism are made by this archive.