Altered state of consciousnessAn altered state of consciousness (ASC), also called altered state of mind or mind alteration, is any condition which is significantly different from a normal waking state. By 1892, the expression was in use in relation to hypnosis, though there is an ongoing debate as to whether hypnosis is to be identified as an ASC according to its modern definition. The next retrievable instance, by Max Mailhouse from his 1904 presentation to conference, however, is unequivocally identified as such, as it was in relation to epilepsy, and is still used today.
Astral projectionAstral projection (also known as astral travel) is a term used in esotericism to describe an intentional out-of-body experience (OBE) that assumes the existence of a subtle body, known as the astral body or body of light, through which consciousness can function separately from the physical body and travel throughout the astral plane. The idea of astral travel is ancient and occurs in multiple cultures. The term "astral projection" was coined and promoted by 19th-century Theosophists.
ParanormalParanormal events are purported phenomena described in popular culture, folk, and other non-scientific bodies of knowledge, whose existence within these contexts is described as being beyond the scope of normal scientific understanding. Notable paranormal beliefs include those that pertain to extrasensory perception (for example, telepathy), spiritualism and the pseudosciences of ghost hunting, cryptozoology, and ufology.
Near-death experienceA near-death experience (NDE) is a profound personal experience associated with death or impending death which researchers describe as having similar characteristics. When positive, which the great majority are, such experiences may encompass a variety of sensations including detachment from the body, feelings of levitation, total serenity, security, warmth, joy, the experience of absolute dissolution, review of major life events, the presence of a light, and seeing dead relatives.
ClairvoyanceClairvoyance (klɛərˈvɔɪ.əns; ) is the claimed psychic ability to gain information about an object, person, location, or physical event through extrasensory perception. Any person who is claimed to have such ability is said to be a clairvoyant (klɛərˈvɔɪ.ənt) ("one who sees clearly"). Claims for the existence of paranormal and psychic abilities such as clairvoyance have not been supported by scientific evidence. Parapsychology explores this possibility, but the existence of the paranormal is not accepted by the scientific community.
Sleep paralysisSleep paralysis is a state, during waking up or falling asleep, in which one is conscious but is unable to move or speak. During an episode, one may hallucinate (hear, feel, or see things that are not there), which often results in fear. Episodes generally last no more than a few minutes. It can recur multiple times or occur as a single episode. The condition may occur in those who are otherwise healthy or those with narcolepsy, or it may run in families as a result of specific genetic changes.
TranceTrance 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. The term trance may be associated with hypnosis, meditation, magic, flow, prayer, and altered states of consciousness.
Depersonalization-derealization disorderDepersonalization-derealization disorder (DPDR, DPD) is a mental disorder in which the person has persistent or recurrent feelings of depersonalization and/or derealization. Depersonalization is described as feeling disconnected or detached from one's self. Individuals may report feeling as if they are an outside observer of their own thoughts or body, and often report feeling a loss of control over their thoughts or actions. Derealization is described as detachment from one's surroundings.
HallucinogenHallucinogens are a large and diverse class of psychoactive drugs that can produce altered states of consciousness characterized by major alterations in thought, mood, and perception as well as other changes. Most hallucinogens can be categorized as either being psychedelics, dissociatives, or deliriants. The word hallucinogen is derived from the word hallucination. The term hallucinate dates back to around 1595–1605, and is derived from the Latin hallūcinātus, the past participle of (h)allūcināri, meaning "to wander in the mind.
Martin GardnerMartin Gardner (October 21, 1914 May 22, 2010) was an American popular mathematics and popular science writer with interests also encompassing scientific skepticism, micromagic, philosophy, religion, and literature - especially the writings of Lewis Carroll, L. Frank Baum, and G. K. Chesterton. He was also a leading authority on Lewis Carroll. The Annotated Alice, which incorporated the text of Carroll's two Alice books, was his most successful work and sold over a million copies.