- Also known as apparitional experience. Both terms stem from the Latin verb apparere,which means to appear or to manifest (itself). The term apparition has various connotations, the most important of which are (1) a "visual illusion or hallucination, (2) the perceived manifestation of a living person or animal normally outside the range of regular sense perception, and (3) the perceived manifestation of a dead person or animal (traditionally regarded as a ghost or spirit). The common descent of these three sets of connotations is apparent in the 19th century literature, notably in the Essay towards a theory of apparitions by the British physician John Fer-riar (1761-1815). Ferriar's Essay has been heralded as the first text that examines hallucinations from a purely physiological point of view. Although it is true that in this work Ferriar seeks to clarify " visual hallucinations by exclusive reference to natural principles, he still focuses on stories of ghosts and spirits. Parapsychologists tend to distinguish various types of apparitions. An example of a four-factor model, used by the British mathematician and parapsychologist George Nugent Merle Tyrrell (1897-1952), comprises (1) experimental cases (in which an agent deliberately makes itself visible), (2) crisis cases or crisis apparitions (consisting of apparitions coinciding with a crisis experienced by a person connected with those apparitions), (3) postmortem cases (appearing long after the individual in question has died), and (4) ghosts (i.e. apparitions which habitually haunt certain places). An example of a seven-factor model is provided by the American paranormal researcher Rosemary Ellen Guily. Her model comprises (1) crisis apparitions (i.e. occurring in times of crisis, often of a warning nature), (2) apparitions of the dead (i.e. depicting dead or dying people), (3) collective apparitions (i.e. focussing on various individuals simultaneously), (4) reciprocal apparitions (i.e. where the affected individual has the impression of communicating with a dead or living agent), (5) "veridical apparitions (which can allegedly be corroborated empirically), (6) deathbed apparitions (also referred to as " take-away apparitions, to denote the beings that may figure in "deathbed visions and are believed to summon or escort the dying person from this world into the afterlife), and (7) apparitions suggestive of reincarnation. Apparitions have been reported and recorded since ancient times. Characteristics attributed to them in a greater or lesser degree include their non-physical nature, their possible appearance in " collective percipience, and a remarkable tendency to imitate regular sensory percepts (mostly consisting of individuals wearing clothes, but also of animals such as horses, cats, or dogs). Moreover, many apparitions are reportedly preceded by a feeling of " sensed presence and accompanied by a feeling of cold. As to their spatial characteristics, it is assumed that apparitions can appear either in physical, extracorporeal space (although many parapsychologists hold that they never bind to physical objects) or in a special space of their own (such as a polished surface, a part of the wall, a mirror, a crystal, or a dream). A third possibility described in the paranormal literature is that the percipient is 'drawn into' the apparition's surroundings and therefore perceives it in its 'natural habitat'. The first large-scale study devoted to apparitions was carried out by the British founders of the Society for Psychical Research (SPR) Edmund Gurney (18471888), Frederic Myers (1843-1901), and Frank Podmore (1856-1910), who collected 5,700 firsthand descriptions of apparitions and published these in their 1886 Phantasms of the living.The first systematic study of apparitions in the general population was the late 19th century "Census of Hallucinations, in which 27,329 individuals were polled in Great Britain, Germany, France, and the United States. Explanatory models pertaining to the nature and origin of apparitions vary widely. Biomedical models tend to use the terms "complex visual hallucination, "compound hallucination, or "personification to denote these phenomena, explaining their mediation by reference to aberrant neurophysiological activity in cerebral areas such as the parietal cortex, the hippocampus, the pedunculus cerebri, and/or the temporo-parieto-occipital junction. Parapsycho-logical models tend to combine such biomedical explanations with hypotheses related to a metaphysical origin of the perceived apparitions. Gurney, for example, conjectured that apparitions could be caused by the telepathic powers of dead or living agents, while Myers speculated that Man's 'subliminal self' might be receptive to extrasensory input stimuli. To suspend judgement on the issue of whether apparitions exist or not, it has been proposed to use the neutral term " idionecrophany to denote any sensory experience that involves an alleged contact with the dead. As noted by the British historian of psychiatry German Berrios, the notion of the apparition can be regarded as a conceptual precursor of the notion of hallucination. This is perhaps exemplified most clearly by the book Ueber die Phantastischen Gesichtserscheinungen, published in 1826 by the German physiologist and zoologist Johannes Peter Müller (1801-1858).ReferencesFerriar, J. (1813). An essay towards a theory of apparitions. London: Cadell and Davies.Müller, J. (1826). Ueber die phantastischen Gesichtserscheinungen. Koblenz: Hölscher.Gurney, E., Myers, F.W.H., Podmore, F. (1886). Phantasms of the living. Volumes 1 and 2. London: The Society for Psychical Research.Tyrrell, G.N.M. (1953). Apparitions. Revised edition. London: The Society for Psychical Research.Guily, R.E. (1991). Harper's encyclopedia of mystical and paranormal experience.New York, NY: Castle Books.Berrios, G.E. (2005). On the fantastic apparitions of vision by Johannes Müller. History of Psychiatry, 16, 229-246.
Dictionary of Hallucinations. J.D. Blom. 2010.