Trance is a state of semi-consciousness in which a person is not self-aware and is either altogether unresponsive to external stimuli (but nevertheless capable of pursuing and realizing an aim) or is selectively responsive in following the directions of the person (if any) who has induced the trance. Trance states may occur involuntarily and unbidden.

Dissociative trance
Collier-priestess of Delphi.jpg
The Oracle at Delphi was famous for her divinatory trances throughout the ancient Mediterranean world. Oil painting, John Collier, 1891

The term trance may be associated with hypnosis, meditation, magic, flow, prayer, and altered states of consciousness.


Trance in its modern meaning comes from an earlier meaning of "a dazed, half-conscious or insensible condition or state of fear", via the Old French transe "fear of evil", from the Latin transīre "to cross", "pass over".[1]

Working modelsEdit

Wier, in his 1995 book, Trance: from magic to technology, defines a simple trance (p. 58) as a state of mind being caused by cognitive loops where a cognitive object (a thought, an image, a sound, an intentional action) repeats long enough to result in various sets of disabled cognitive functions. Wier represents all trances (which include sleep and watching television) as taking place on a dissociated trance plane where at least some cognitive functions such as volition are disabled; as is seen in what is typically termed a 'hypnotic trance'.[2] With this definition, meditation, hypnosis, addictions and charisma are seen as being trance states. In Wier's 2007 book, The Way of Trance, he elaborates on these forms, adds ecstasy as an additional form and discusses the ethical implications of his model, including magic and government use which he terms "trance abuse".

John Horgan in Rational Mysticism (2003) explores the neurological mechanisms and psychological implications of trances and other mystical manifestations. Horgan incorporates literature and case-studies from a number of disciplines in this work: chemistry, physics, psychology, radiology and theology.

Trance statesEdit

Trance conditions include all the different states of mind, emotions, moods and daydreams that human beings experience. All activities which engage a human involve the filtering of information coming into sense modalities, and this influences brain functioning and consciousness. Therefore, trance may be understood as a way for the mind to change the way it filters information in order to provide more efficient use of the mind's resources.

Trance states may also be accessed or induced by various modalities and may be a way of accessing the unconscious mind for the purposes of relaxation, healing, intuition and inspiration. There is an extensive documented history of trance as evidenced by the case-studies of anthropologists and ethnologists and associated and derivative disciplines. Hence trance may be perceived as endemic to the human condition and a Human Universal. Principles of trance are being explored and documented as are methods of trance induction. Benefits of trance states are being explored by medical and scientific inquiry. Many traditions and rituals employ trance. Trance also has a function in religion and mystical experience.

Castillo (1995) states that: "Trance phenomena result from the behavior of intense focusing of attention, which is the key psychological mechanism of trance induction. Adaptive responses, including institutionalized forms of trance, are 'tuned' into neural networks in the brain and depend to a large extent on the characteristics of culture. Culture-specific organizations exist in the structure of individual neurons and in the organizational formation of neural networks."[3]

Hoffman (1998: p. 9) states that: "Trance is still conventionally defined as a state of reduced consciousness, or a somnolent state. However, the more recent anthropological definition, linking it to 'altered states of consciousness' (Charles Tart), is becoming increasingly accepted."[4]

Hoffman (1998, p. 9) asserts that: "...the trance state should be discussed in the plural, because there is more than one altered state of consciousness significantly different from everyday consciousness."[4]


Temple of Epidaurus: healing sleepEdit

According to Hoffman (1998: p. 10), pilgrims visited the Temple of Epidaurus, an asclepeion, in Greece for healing sleep. Seekers of healing would make pilgrimage and be received by a priest who would welcome and bless them. This temple housed an ancient religious ritual promoting dreams in the seeker that endeavored to promote healing and the solutions to problems, as did the oracles. This temple was built in honor of Asclepios, the Greek god of medicine. The Greek treatment was referred to as incubation, and focused on prayers to Asclepios for healing. The asclepion at Epidaurus is both extensive and well-preserved, and is traditionally regarded as the birthplace of Asclepius. (For a comparable modern tool see Dreamwork.)

Oracle at DelphiEdit

The Oracle at Delphi was also famous for trances in the ancient Greek world; priestesses there would make predictions about the future in exchange for gold.[5]

Oral lore and storytellingEdit

Stories of the saints in the Middle Ages, myths, parables, fairy tales, oral lore and storytelling from different cultures are themselves potentially inducers of trance. Often literary devices such as repetition are employed which is evident in many forms of trance induction. Milton Erickson used stories to induce trance as do many NLP practitioners.


The Spartans were the first to utilize music on the way to battle. They played songs from the flute and sang, which put them into a fearless state for fighting. From at least the 16th century it was held that march music may induce soldiers marching in unison into trance states where according to apologists, they bond together as a unit engendered by the rigors of training, the ties of comradeship and the chain of command. This had the effect of making the soldiers become automated, an effect which was widely evident in the 16th, 17th and 18th century due to the increasing prevalence of firearms employed in warcraft. Military instruments, especially the snare drum and other drums were used to entone a monotonous ostinato at the pace of march and heartbeat. High-pitched fifes, flutes and bagpipes were used for their "piercing" effect to play the melody. This would assist the morale and solidarity of soldiers as they marched to battle.

Joseph Jordania recently proposed a term battle trance for this mental state, when combatants do not feel fear and pain, and when they lose their individual identity and acquire a collective identity.[6]

The Norse Berserkers induced a trance-like state before battle, called Berserkergang. It is said to have given the warriors superhuman strength and made them impervious to pain during battle. This form of trance could have been induced partly due to ingestion of hallucinogenic mushrooms.


As the mystical experience of mystics generally entails direct connection, communication and communion with the divine; trance and cognate experience are endemic. (see Yoga, Sufism, Shaman, Umbanda, Crazy Horse, etc.)

As shown by Jonathan Garb,[7] trance techniques also played a role in Lurianic Kabbalah, the mystical life of the circle of Moshe Hayyim Luzzatto and Hasidism.

Christian mysticsEdit

Many Christian mystics are documented as having experiences that may be considered as cognate with trance, such as: Hildegard of Bingen, John of the Cross, Meister Eckhart, Saint Theresa (as seen in the Bernini sculpture) and Francis of Assisi.

Mesmer and the origin of hypnotherapyEdit

  • Mesmer, an influential but discredited promoter of trance states and their curative powers.
  • Milton Erickson, the founder of hypnotherapy who introduced trance and hypnosis to orthodox medicine and psychotherapy—hypnosis here is something different from traditional clinical hypnosis.

Trance in American ChristianityEdit

Taves (1999) charts the synonymic language of trance in the American Christian traditions: power or presence or indwelling of God, or Christ, or the Spirit, or spirits. Typical expressions include "the indwelling of the Spirit" (Jonathan Edwards), "the witness of the Spirit" (John Wesley), "the power of God" (early American Methodists), being "filled with the Spirit of the Lord" (early Adventists; see charismatic Adventism), "communing with spirits" (Spiritualists), "the Christ within" (New Thought), "streams of holy fire and power" (Methodist holiness), "a religion of the Spirit and Power" (the Emmanuel Movement), and "the baptism of the Holy Spirit" (early Pentecostals). (Taves, 1999: 3)

Trance and Anglo-American ProtestantsEdit

Taves (1999) well-referenced book on trance charts the experience of Anglo-American Protestants and those who left the Protestant movement beginning with the transatlantic awakening in the early 18th century and ending with the rise of the psychology of religion and the birth of Pentecostalism in the early 20th century. This book focuses on a class of seemingly involuntary acts alternately explained in religious and secular terminology. These involuntary experiences include uncontrolled bodily movements (fits, bodily exercises, falling as dead, catalepsy, convulsions); spontaneous vocalizations (crying out, shouting, speaking in tongues); unusual sensory experiences (trances, visions, voices, clairvoyance, out-of-body experiences); and alterations of consciousness and/or memory (dreams, somnium, somnambulism, mesmeric trance, mediumistic trance, hypnosis, possession, alternating personality) (Taves, 1999: 3).

Trance induction and sensory modalityEdit

Trance-like states are often interpreted as religious ecstasy or visions and can be deliberately induced using a variety of techniques, including prayer, religious rituals, meditation, pranayama (breathwork or breathing exercises), physical exercise, sexual intercourse, music, dancing, sweating (e.g. sweat lodge), fasting, thirsting, and the consumption of psychotropic drugs such as cannabis. Sensory modality is the channel or conduit for the induction of the trance. Sometimes an ecstatic experience takes place in occasion of contact with something or somebody perceived as extremely beautiful or holy. It may also happen without any known reason. The particular technique that an individual uses to induce ecstasy is usually one that is associated with that individual's particular religious and cultural traditions. As a result, an ecstatic experience is usually interpreted within the context of a particular individual's religious and cultural traditions. These interpretations often include statements about contact with supernatural or spiritual beings, about receiving new information as a revelation, also religion-related explanations of subsequent change of values, attitudes and behavior (e.g. in case of religious conversion).

Benevolent, neutral and malevolent trances may be induced (intentionally, spontaneously and/or accidentally) by different methods:

Auditory driving and auditory artEdit

Charles Tart provides a useful working definition of auditory driving. It is the induction of trance through the sense of hearing. Auditory driving works through a process known as entrainment.[citation needed]

The usage of repetitive rhythms to induce trance states is an ancient phenomenon. Throughout the world, shamanistic practitioners have been employing this method for millennia. Anthropologists and other researchers have documented the similarity of shamanistic auditory driving rituals among different cultures.

Said simply, entrainment is the synchronization of different rhythmic cycles. Breathing and heart rate have been shown to be affected by auditory stimulus, along with brainwave activity. The ability of rhythmic sound to affect human brainwave activity, especially theta brainwaves, is the essence of auditory driving, and is the cause of the altered states of consciousness that it can induce.[citation needed]

Visual driving and visual artEdit

Nowack and Feltman published an article entitled "Eliciting the Photic Driving Response" which states that the EEG photic driving response is a sensitive neurophysiological measure which has been employed to assess chemical and drug effects, forms of epilepsy, neurological status of Alzheimer's patients, and physiological arousal. Photic driving also impacts upon the psychological climate of a person by producing increased visual imagery and decreased physiological and subjective arousal. In this research by Nowack and Feltman, all participants reported increased visual imagery during photic driving, as measured by their responses to an imagery questionnaire.

Dennis Wier[8] states that over two millennia ago Ptolemy and Apuleius found that differing rates of flickering lights affected states of awareness and sometimes induced epilepsy. Wier also asserts that it was discovered in the late 1920s that when light was shined on closed eyelids it resulted in an echoing production of brainwave frequencies. Wier also opined that in 1965 Grey employed a stroboscope to project rhythmic light flashes into the eyes at a rate of 10–25 Hz (cycles per second). Grey discovered that this stimulated similar brainwave activity.

Research by Thomas Budzynski, Oestrander et al., in the use of brain machines suggest that photic driving via the suprachiasmatic nucleus and direct electrical stimulation and driving via other mechanisms and modalities, may entrain processes of the brain facilitating rapid and enhanced learning, produce deep relaxation, euphoria, an increase in creativity, problem solving propensity and may be associated with enhanced concentration and accelerated learning. The theta range and the border area between alpha and theta has generated considerable research interest.

Kinesthetic driving and somatic artEdit

Charles Tart provides a useful working definition of kinesthetic driving. It is the induction of trance through the sense of touch, feeling or emotions. Kinesthetic driving works through a process known as entrainment.

The rituals practiced by some athletes in preparing for contests are dismissed as superstition, but this is a device of sport psychologists to help them to attain an ecstasy-like state. Joseph Campbell had a peak experience whilst running. Roger Bannister on breaking the four-minute mile (Cameron, 1993: 185): "No longer conscious of my movement, I discovered a new unity with nature. I had found a new source of power and beauty, a source I never dreamt existed." Roger Bannister later became a distinguished neurologist.

Mechanisms and disciplines that include kinesthetic driving may include: dancing, walking meditation, yoga and asana, mudra, juggling, poi (juggling), etc.

Sufism (the mystical branch of Islam) has theoretical and metaphoric texts regarding ecstasy as a state of connection with Allah. Sufi practice rituals (dhikr, sema) use body movement and music to achieve the state.

Types and varietiesEdit

  • Maenads and Bacchae: in Greek mythology, Maenads were female worshippers of Dionysus, the Greek god of mystery, wine and intoxication, and the Roman god Bacchus. The word literally translates as "raving ones". They were known as wild, insane women who could not be reasoned with. The mysteries of Dionysus inspired the women to ecstatic frenzy; they indulged in copious amounts of violence, bloodletting, sexual activity, self-intoxication, and mutilation. They were usually pictured as crowned with vine leaves, clothed in fawnskins and carrying the thyrsus, and dancing with wild abandon. They were also characterized as entranced women, wandering through the forests and hills.[9] The Maenads were also known as Bassarids (or Bacchae or Bacchantes) in Roman mythology, after the penchant of the equivalent Roman god, Bacchus, to wear a fox-skin, a bassaris.
  • Norse berserkers were said to have often entered battle entrenched in a state of primal rage, biting their shields and howling like wolves. This fanaticism was so powerful that they were known to continue fighting even after having lost limbs or being otherwise deeply wounded.
  • Samādhi: yoga provides techniques to attain a state of ecstasy called samādhi. According to practitioners, there are various stages of ecstasy, the highest of which is called Nirvikalpa samādhi. Different traditions have different understanding of Samādhi.[10]
  • Bhakti: (Devanāgarī: भक्ति) is a word of Sanskrit origin meaning "devotion" and also "the path of devotion" itself, as in Bhakti-yoga. Within Hinduism the word is used exclusively to denote devotion to a particular deity or form of God. Within Vaishnavism bhakti is only used in conjunction with Vishnu or one of his associated incarnations, it is likewise used towards Shiva by followers of Shaivism. Saints in these traditions exhibit different trance states or ecstasy.
  • Agape or "Divine Love": the term agape appears in the Odyssey twice, where the word describes something that creates contentedness within the speaker.
  • Communion: In the monotheistic tradition, religious ecstasy is usually associated with communion and oneness with God. Indeed, ecstasy is the primary vehicle for the type of prophetic visions and revelations found in the Bible. However, such experiences can also be personal mystical experiences with no significance to anyone but the person experiencing them.
  • Rapture or religious ecstasy: is an altered state of consciousness characterized by greatly reduced external awareness and expanded interior mental and spiritual awareness which is frequently accompanied by visions and emotional/intuitive (and sometimes physical) euphoria. Although the experience is usually brief in physical time, there are records of such experiences lasting several days or even more, and of recurring experiences of ecstasy during one's lifetime. Subjective perception of time, space and/or self may strongly change or disappear during ecstasy.
  • Peak experiences: is a term developed by Abraham Maslow and used to describe certain extra-personal and ecstatic states, particularly ones tinged with themes of unification, harmonization and interconnectedness. Participants characterize these experiences, and the revelations imparted therein, as possessing an ineffably mystical (or overtly religious) quality or essence.
  • In Christianity, the ecstatic experiences of the Apostles Peter and Paul are recorded in Acts 10:10, 11:5 and 22:17.
  • Some charismatic Christians practice ecstatic states (called, e.g., "being slain in the Spirit") and interpret these as given by the Holy Spirit.
  • In hagiography (writings on the subject of Christian saints) many instances are recorded in which saints are granted ecstasies. According to the Catholic Encyclopedia,[11] religious ecstasy (called supernatural ecstasy) includes two elements: one, interior and invisible, in which the mind rivets its attention on a religious subject, and another, corporeal and visible, in which the activity of the senses is suspended, reducing the effect of external sensations upon the subject and rendering him or her resistant to awakening.
  • Trance states have also long been used by shamans, mystics, and fakirs in healing rituals, being particularly cultivated in some religions, such as Tibetan Buddhism. Australian shamanism has been observed[12][13]


Divination is a cultural universal which anthropologists have observed as being present in many religions and cultures in all ages up to the present day (see sibyl).[citation needed] Divination may be defined as a mechanism for fortune-telling by ascertaining information by interpretation of omens or an alleged supernatural agency. Divination often entails ritual, and is often facilitated by trance.

Nechung OracleEdit

In Tibet, oracles have played, and continue to play, an important part in religion and government. The word oracle is used by Tibetans to refer to the spirit, deity or entity that enters those men and women who act as media between the natural and the spiritual realms. The media are, therefore, known as kuten, which literally means, "the physical basis".

The Dalai Lama, who lives in exile in northern India, still consults an oracle known as the Nechung Oracle, which is considered the official state oracle of the government of Tibet. He gives a complete description of the process of trance and possession in his book Freedom in Exile.[14]

Scientific disciplinesEdit

Convergent disciplines of neuroanthropology, ethnomusicology, electroencephalography (EEG), neurotheology and cognitive neuroscience, amongst others, are conducting research into the trance induction of altered states of consciousness resulting from neuron entrainment with the driving of sensory modalities, for example polyharmonics, multiphonics, and percussive polyrhythms through the channel of the auditory and kinesthetic modality.[15]

Neuroanthropology and cognitive neuroscience are conducting research into the trance induction of altered states of consciousness (possibly engendering higher consciousness) resulting from neuron firing entrainment with these polyharmonics and multiphonics. Related research has been conducted into neural entraining with percussive polyrhythms. The timbre of traditional singing bowls and their polyrhythms and multiphonics are considered meditative and calming, and the harmony inducing effects of this tool to potentially alter consciousness are being explored by scientists, medical professionals and therapists.[citation needed]

Brainwaves and brain rhythmsEdit

Scientific advancement and new technologies such as computerized EEG, positron emission tomography, regional cerebral blood flow, and nuclear magnetic resonance imaging, are providing measurable tools to assist in understanding trance phenomena.

There are four principal brainwave states that range from high-amplitude, low-frequency delta to low-amplitude, high-frequency beta. These states range from deep dreamless sleep to a state of high arousal. These four brainwave states are common throughout humans. All levels of brainwaves exist in everyone at all times, even though one is foregrounded depending on the activity level. When a person is in an aroused state and exhibiting a beta brainwave pattern, their brain also exhibits a component of alpha, theta and delta, even though only a trace may be present.[16]

The University of Philadelphia study on some Christians at the Freedom Valley Worship Center in Gettysburg, Pennsylvania, revealed that glossolalia-speaking (vocalizing or praying in unrecognizable form of language which is seen in members of certain Christian sects) activates areas of the brain out of voluntary control. In addition, the frontal lobe of the brain, which monitors speech, significantly diminished in activity as the study participants spoke glossolalia.[17] Dr. Andrew B. Newberg, in analysis of his earlier studies as opposed to the MRI scans of the test subjects, stated that Buddhist monks in meditation[18] and Franciscan nuns in prayer[19] exhibited increased activity in the frontal lobe, and subsequently their behaviors, very much under voluntary control. The investigation found this particular beyond-body-control characteristic only in tongue-speakers (also see xenoglossia).

See alsoEdit


  1. ^ "Online Etymology Dictionary". Retrieved 7 November 2012.
  2. ^ "Archived copy". Archived from the original on 8 December 2009. Retrieved 24 July 2009.CS1 maint: archived copy as title (link)
  3. ^ Castillo, Richard J. (1995). Culture, Trance, and the Mind-Brain. In Anthropology of Consciousness. Volume 6, Number 1, March 1995, pp. 17–34.
  4. ^ a b Hoffman, Kay (1998). The Trance Workbook: understanding & using the power of altered states. Translated by Elfie Homann, Clive Williams, and Dr Christliebe El Mogharbel. Translation edited by Laurel Ornitz. ISBN 0-8069-1765-2 p. 9
  5. ^ Diodorus Siculus 16.26.1–4.
  6. ^ Joseph Jordania, Why do People Sing? Music in Human Evolution. Logos, 2011
  7. ^ (Shamanic Trance in Modern Kabbalah, 2011)
  8. ^ Wier, Dennis R. (15 September 2006). "A Suggested Model for Trance". The Trance Institute. Archived from the original on 15 September 2006. Retrieved 26 February 2021.
  9. ^ Wiles, David (2000). Greek Theatre Performance: An Introduction. Cambridge University Press. Source: [1]
  10. ^ Sarbacker, Stuart Ray (2012). Samadhi: The Numinous and Cessative in Indo-Tibetan Yoga. SUNY Press. p. 13.
  12. ^ Lawlor (1991: p. 374) states that: "The supernormal, super sensory powers of Aboriginal wise woman and men of high degree, by their own accounts, comes directly from initiations administered by the ancestral sky heroes themselves and by the totemic spirits. Those who have gone through these initiations alone, in a deep trance that makes them lose their personal identities and confront manifestations of the ancestral powers, are held in the highest regard."
  13. ^ Lawlor (1991: p. 303) states that: "One such animal dance ceremony was observed and photographed by Gillen and Spencer. More than 30 naked men gathered in a large circle. One by one, each man performed the dance of the animal to be hunted while the others sang and slapped their buttocks to create a percussive beat for the dancer. The slapping sound was so loud that it could be heard for miles across the surrounding desert. The dance continued for hours, with each man dancing frenetically until he dropped from exhaustion. The eyes of the onlookers soon became glazed with entrancement; their penises were erect in a state of ecstatic arousal. Finally, after the last man had performed the animal dance and collapsed in exhaustion, the entire group leaped on him, emitting a loud abandoned cry. The next day the hunt began."
  14. ^ "Archived copy". Archived from the original on 5 December 2006. Retrieved 23 January 2007.CS1 maint: archived copy as title (link)
  15. ^ "Les étranges pouvoirs de la transe sur le cerveau étudiés à l'université". Le (in French). 18 November 2021. Retrieved 20 November 2021.
  16. ^ "What is the function of the various brainwaves?". Scientific American. Retrieved 4 April 2019.
  17. ^ Newberg A, Wintering NA, Morgan D, Waldman MR. The measurement of regional cerebral blood flow during glossolalia: A preliminary SPECT study. Psychiatry Research: Neuroimaging 148(1):67–71, 2006.
  18. ^ Newberg AB, Alavi A, Baime M, Pourdehnad M, Santanna J, d'Aquili EG. The measurement of regional cerebral blood flow during the complex cognitive task of meditation: A preliminary SPECT study. Psychiatry Research: Neuroimaging 106: 113–122, 2001.
  19. ^ Newberg A, Pourdehnad M, Alavi A, d’Aquili E. Cerebral blood flow during meditative prayer: Preliminary findings and methodological issues. Perceptual and Motor Skills 97: 625–630, 2003.

Further readingEdit

  • Cameron, Julia (1993). The Artist's Way. Oxford, London: Pan Books. ISBN 0-330-34358-0
  • Castillo, Richard J. (1995). Culture, Trance, and the Mind-Brain. In Anthropology of Consciousness. Volume 6, Number 1, March 1995, pp. 17–34.* Horgan, John (2003). Rational Mysticism: Dispatches from the Border Between Science and Spirituality. New York: Houghton Mifflin.
  • Goodman, Felicitas D. (1999). Ritual Body Postures, Channeling, and the Ecstatic Body Trance. In Anthropology of Consciousness. Volume 10, Number 1 (March 1999).
  • Heinze, Ruth-Inge (1994). Applications of Altered States of Consciousness in Daily Life. In Anthropology of Consciousness. Volume 5, Number 3, September 1994, pp. 8–12.
  • Hoffman, Kay (1998). The Trance Workbook: understanding & using the power of altered states. Translated by Elfie Homann, Clive Williams, and Dr Christliebe El Mogharbel. Translation edited by Laurel Ornitz. ISBN 0-8069-1765-2
  • Hubbard, Timothy L. (2003). Some Correspondences and Similarities of Shamanism and Cognitive Science: Interconnectedness, Extension of Meaning, and Attribution of Mental States. In Anthropology of Consciousness. Volume 14, Number 1, March–June 2003, pp. 26–45
  • Inglis, Brian (1990). Trance: A Natural History of Altered States of Mind. London, Paladin. ISBN 0-586-08933-0
  • James, William The varieties of religious experience (1902) ISBN 0-14-039034-0
  • Lawlor, Robert (1991). Voices of the First Day: Awakening in the Aboriginal dreamtime. Rochester, Vermont: Inner Traditions International, Ltd. ISBN 0-89281-355-5
  • Lewis, I.M. (2003). Trance, Possession, Shamanism and Sex. In Anthropology of Consciousness. Volume 14, Number 1, March–June 2003, pp. 20–39.
  • McDaniel, June (1989). The Madness of the Saints: Ecstatic Religion in Bengal. University of Chicago Press. ISBN 0-226-55723-5 (Paper); 0-226-55722-7 (Cloth) & ISBN 978-0-226-55723-6 (Paper); 978-0-226-55722-9 (Cloth).
  • Michaelson, Jay (1997). "Paths to the Divine: Ecstatics and Theology in R. Dov Baer of Lubavitch" (6 December 2006)
  • Narr. Maybrey, Vicki. "Speaking in Tongues Medical Study proves Holy Spirit praying." Nightline. ABC. Gettysburg, Philadelphia, 17 July. 2008.
  • Neophytou, Charles (1996). The Encyclopedia of Mind Body and Spirit. Millennium Edition. Yanchep, Western Australia: Lindlahr Book Publishing. ISBN 0-646-26789-2
  • Nowack, William J & Feltman, Mary L. (date?) "Eliciting the Photic Driving Response". American Journal of Electroneurodiagnostic Technology. Vol. 38, No. 1, pp. 43–45.
  • Rich, Grant Jewell (2001). Domestic Paths to Altered States and Transformations of Consciousness. Volume 12, Number 2 (September–December 2001).
  • Smith, Huston (2000). Cleansing the Doors of Perception: The Religious Significance of Entheogenic Plants and Chemicals. Tarcher/Putnam, ISBN 1-58542-034-4, Council on Spiritual Practices, ISBN 1-889725-03-X
  • Tart, Charles T., editor. Altered States of Consciousness (1969) ISBN 0-471-84560-4
  • Tart, Charles T. States of Consciousness (2001) ISBN 0-595-15196-5
  • Taves, Ann (1999). Fits, Trances, & Visions: Experiencing Religion and Explaining Experience from Wesley to James. Princeton, New Jersey: Princeton University Press.
  • Vitebsky, Piers, The Shaman: Voyages of the Soul – Trance, Ecstasy and Healing from Siberia to the Amazon, Duncan Baird, 2001. ISBN 1-903296-18-8
  • Von Gizycki, H., Jean-Louis, G., Snyder, M., Zizi, F., Green, H., Giuliano, V., Spielman, A., Taub, H. (1998). "The effects of photic driving on mood states" in Journal of Psychosomatic Research. Vol. 44, N. 5, pp. 599–604. New York, NY: Elsevier. ISSN 0022-3999
  • Vyner, Henry M. (2002). The Descriptive Mind Science of Tibetan Buddhist Psychology and the Nature of the Healthy Human Mind. In Anthropology of Consciousness. Volume 13, Number 2, September–December 2002, pp. 1–25.
  • Wallis, Robert (1999). Altered States, Conflicting Cultures: Shamans, Neo-Shamans and Academics. In Anthropology of Consciousness. Volume 10, Numbers 2–3 (June–September 1999).
  • Warren, Jeff (2007). "The Trance". The Head Trip: Adventures on the Wheel of Consciousness. Toronto: Random House Canada. ISBN 978-0-679-31408-0.* Wier, Dennis R. Trance: from magic to technology (1995) ISBN 1-888428-38-4
  • Wier, Dennis R. (2007). The Way of Trance Laytonville, California: Trance Research Foundation. ISBN 978-1-888428-10-0.
  • Wilde, Stuart. (1996). The Art of Meditation. Carlsbad: Hay House. ISBN 978-1-56170-530-6

External linksEdit