American psychologist and philosopher William James (1842–1910) was an early psychical researcher.^[1]

The term parapsychology was coined in or around 1889 by philosopher Max Dessoir, and originates from para meaning "alongside", and psychology. The term was adopted by J.B. Rhine in the 1930s as a replacement for the term psychical research.^[2] Parapsychologists study a number of ostensible paranormal phenomena, including telepathy, precognition, clairvoyance, psychokinesis, near-death experiences, reincarnation and apparitional experiences.

Parapsychology research is conducted in some 30 different countries.^[3] Laboratory and field research is conducted through private institutions and universities.^[4] Privately-funded units in psychology departments at universities in the United Kingdom are among the most active today.^[5] In the United States, interest in research peaked in the 1970s and university-based research has declined since then, although private institutions still receive funding from donations.^[6] While parapsychological research has occasionally appeared in mainstream academic journals,^{[7][8][9][10]} most of the recent research is published in a small number of niche journals.^[11] Journals dealing with parapsychology include the Journal of Parapsychology, Journal of Near-Death Studies, Journal of Consciousness Studies, Journal of the Society for Psychical Research and Journal of Scientific Exploration.

The Parapsychological Association regards the results of parapsychologists' experiments as having demonstrated the existence of some forms of psychic abilities,^[12] and proponents of parapsychology have seen it as an "embryo science",^[13] a "frontier science of the mind",^[14] and a "frontier discipline for advancing knowledge".^[15] However, critics argue that methodological flaws can explain any apparent experimental successes^[16] and the status of parapsychology as a science has been vigorously disputed.^[17] Many scientists regard the discipline as pseudoscience as they claim that parapsychologists continue investigation despite not having demonstrated conclusive evidence of psychic abilities in more than a century of research.^[18][19][20] Nobel Laureate Brian David Josephson and some other proponents of parapsychology have spoken of "irrational attacks on parapsychology" which stem from the difficulties of "putting these phenomena into our present system of the universe".^[13]

Terminology[link]

The term parapsychology was coined in or around 1889 by philosopher Max Dessoir. It was adopted by J.B. Rhine in the 1930s as a replacement for the term psychical research in order to indicate a significant shift toward experimental methodology and academic discipline.^[2] The term originates from the Greek: παρά para meaning "alongside", and psychology.

History[link]

Henry Sidgwick was an English utilitarian philosopher. He was one of the founders and first president of the Society for Psychical Research and a member of the Metaphysical Society.

Thomson Jay Hudson was Chief Examiner of the US Patent Office and Psychical researcher, known for his three laws of psychic phenomena, which were first published in 1893.

Early parapsychological research employed the use of Zener cards in experiments designed to test for the existence of telepathic communication.

Early psychical research[link]

The Society for Psychical Research (SPR) was founded in London in 1882. The formation of the SPR was the first systematic effort to organize scientists and scholars for a critical and sustained investigation of paranormal phenomena. The early membership of the SPR included philosophers, scholars, scientists, educators and politicians, such as Henry Sidgwick, Arthur Balfour, William Crookes, Rufus Osgood Mason and Charles Richet.^[21]

The SPR classified its subjects of study into several areas: telepathy, hypnotism, Reichenbach's phenomena, apparitions, haunts, and the physical aspects of Spiritualism such as table-tilting and the appearance of matter from unknown sources, otherwise known as materialization. One of the first collaborative efforts of the SPR was its Census of Hallucinations, which researched apparitional experiences and hallucinations in the sane. The census was the Society's first attempt at a statistical evaluation of paranormal phenomena, and the resulting publication in 1886, Phantasms of the Living is still widely referenced in parapsychological literature today. The SPR became the model for similar societies in other European countries and the United States during the late 19th century. Largely due to the support of psychologist William James, the American Society for Psychical Research (ASPR) opened its doors in New York City in 1885.^[1] The SPR and ASPR continue research in parapsychology.^[22]

Rhine era[link]

In 1911, Stanford University became the first academic institution in the United States to study extrasensory perception (ESP) and psychokinesis (PK) in a laboratory setting. The effort was headed by psychologist John Edgar Coover. In 1930, Duke University became the second major U.S. academic institution to engage in the critical study of ESP and psychokinesis in the laboratory. Under the guidance of psychologist William McDougall, and with the help of others in the department—including psychologists Karl Zener, Joseph B. Rhine, and Louisa E. Rhine—laboratory ESP experiments using volunteer subjects from the undergraduate student body began. As opposed to the approaches of psychical research, which generally sought qualitative evidence for paranormal phenomena, the experiments at Duke University proffered a quantitative, statistical approach using cards and dice. As a consequence of the ESP experiments at Duke, standard laboratory procedures for the testing of ESP developed and came to be adopted by interested researchers throughout the world.^[1]

The publication of J.B. Rhine's book, New Frontiers of the Mind (1937) brought the laboratory's findings to the general public. In his book, Rhine popularized the word "parapsychology," which psychologist Max Dessoir had coined over 40 years earlier, to describe the research conducted at Duke. Rhine also founded an autonomous Parapsychology Laboratory within Duke and started the Journal of Parapsychology, which he co-edited with McDougall.^[1]

Rhine, along with associate Karl Zener, had developed a statistical system of testing for ESP that involved subjects guessing what symbol, out of five possible symbols, would appear when going through a special deck of cards designed for this purpose. A percentage of correct guesses (or hits) significantly above 20% was perceived as higher than chance and indicative of psychic ability. Rhine stated in his first book, ExtraSensory Perception (1934), that after 90,000 trials, he felt ESP is "an actual and demonstrable occurrence."^[23]

The parapsychology experiments at Duke evoked much criticism from academics and others who challenged the concepts and evidence of ESP. One such criticism was that subjects were simply cheating. Illusionist Milbourne Christopher wrote years later that he felt "there are at least a dozen ways a subject who wished to cheat under the conditions Rhine described could deceive the investigator".^[24] According to Christopher, Rhine did take precautions against cheating in response to criticisms of his methods, but once he did, he was unable to find the same high scores reported in earlier trials.^[24] Another criticism, made by chemist Irving Langmuir, among others, was one of selective reporting. Langmuir stated that Rhine did not report scores of subjects that he suspected were intentionally guessing wrong, and that this, he felt, biased the statistical results higher than they should have been.^[25]

Rhine and his colleagues attempted to address these criticisms through new experiments, articles, and books, and revisited the state of the criticism along with their responses in the book Extra-Sensory Perception After Sixty Years (1940).^[26] In 1957, Rhine and Joseph Gaither Pratt wrote Parapsychology: Frontier Science of the Mind.

The administration of Duke grew less sympathetic to parapsychology, and after Rhine's retirement in 1965 parapsychological links with the university were broken. Rhine later established the Foundation for Research on the Nature of Man (FRNM) and the Institute for Parapsychology as a successor to the Duke laboratory.^[1] In 1995, the centenary of Rhine's birth, the FRNM was renamed the Rhine Research Center. Today, the Rhine Research Center is a parapsychology research unit, stating that it "aims to improve the human condition by creating a scientific understanding of those abilities and sensitivities that appear to transcend the ordinary limits of space and time."^[27]

Establishment of the Parapsychological Association[link]

The Parapsychological Association (PA) was created in Durham, North Carolina, on June 19, 1957. Its formation was proposed by J. B. Rhine at a workshop on parapsychology which was held at the Parapsychology Laboratory of Duke University. Rhine proposed that the group form itself into the nucleus of an international professional society in parapsychology. The aim of the organization, as stated in its Constitution, became "to advance parapsychology as a science, to disseminate knowledge of the field, and to integrate the findings with those of other branches of science".^[28]

Under the direction of anthropologist Margaret Mead, the Parapsychological Association took a large step in advancing the field of parapsychology in 1969 when it became affiliated with the American Association for the Advancement of Science (AAAS), the largest general scientific society in the world.^[29] In 1979, physicist John A. Wheeler argued that parapsychology is pseudoscientific, and that the affiliation of the PA to the AAAS needed to be reconsidered.^[30][31] His challenge to parapsychology's AAAS affiliation was unsuccessful.^[31] Today, the PA consists of about three hundred full, associate, and affiliated members worldwide.^[32]

The 1970s and 1980s[link]

The affiliation of the Parapsychological Association (PA) with the American Association for the Advancement of Science, along with a general openness to psychic and occult phenomena in the 1970s, led to a decade of increased parapsychological research. During this period, other related organizations were also formed, including the Academy of Parapsychology and Medicine (1970), the Institute of Parascience (1971), the Academy of Religion and Psychical Research, the Institute of Noetic Sciences (1973), the International Kirlian Research Association (1975), and the Princeton Engineering Anomalies Research Laboratory (1979). Parapsychological work was also conducted at the Stanford Research Institute (SRI) during this time.^[2]

The scope of parapsychology expanded during these years. Psychiatrist Ian Stevenson conducted much of his research into reincarnation during the 1970s, and the second edition of his Twenty Cases Suggestive of Reincarnation was published in 1974. Psychologist Thelma Moss devoted time to the study of Kirlian photography at UCLA's parapsychology laboratory. The influx of spiritual teachers from Asia, and their claims of abilities produced by meditation, led to research on altered states of consciousness. American Society for Psychical Research Director of Research, Karlis Osis, conducted experiments in out of body experiences. Physicist Russell Targ coined the term remote viewing for use in some of his work at SRI in 1974.^[2]

The surge in paranormal research continued into the 1980s: the Parapsychological Association reported members working in more than 30 countries. For example, research was carried out and regular conferences held in Eastern Europe and the former Soviet Union^[2] although the word parapsychology was discarded in favour of the term "psychotronics".^[33] The promoters of psychotronics was Czech scientist Zdeněk Rejdák. Rejdák kept enforcing the psychotronics as a physical science on the world-wide scale and for many years, he organized conferences on research in psychotronics. The psychotronics of this era is being understood as a new science in the terms of human bionics. The main objectives of psychotronics were to verify and study distant interactions human organism and its information and energy expressions and subsequently the phenomena of telepathy, clairvoyance and psychokinesis, to discover new principles of nature.^[34][35]

In 1985 a Chair of Parapsychology was established within the Department of Psychology at the University of Edinburgh. Robert Morris, a respected experimental parapsychologist from the United States took up the position, and with his research associates and PhD students pursued a comprehensive research programme.^[36] Since Professor Morris' death in 2004 the Chair of Parapsychology has remained vacant.^[37]

More recent developments[link]

Rupert Sheldrake is an English biochemist and plant physiologist. He is known for his research into parapsychology.

Since the 1980s, contemporary parapsychological research has waned considerably in the United States.^[38] Early research was considered inconclusive, and parapsychologists were faced with strong opposition from their academic colleagues.^[2] Some effects thought to be paranormal, for example the effects of Kirlian photography (thought by some to represent a human aura), disappeared under more stringent controls, leaving those avenues of research at dead-ends.^[2] Many university laboratories in the United States have closed, citing a lack of acceptance by mainstream science as the reason;^[38] the bulk of parapsychology research in the US is now confined to private institutions funded by private sources.^[2] After 28 years of research, Princeton Engineering Anomalies Research Laboratory (PEAR), which studied psychokinesis, closed in 2007.^[38]

Two universities in the United States currently have academic parapsychology laboratories. The Division of Perceptual Studies, a unit at the University of Virginia's Department of Psychiatric Medicine, studies the possibility of survival of consciousness after bodily death, near-death experiences, and out-of-body experiences.^[39] The University of Arizona's Veritas Laboratory conducts laboratory investigations of mediums. Several private institutions, including the Institute of Noetic Sciences, conduct and promote parapsychological research.^[38]

Over the last two decades some new sources of funding for parapsychology in Europe have see a "substantial increase in European parapsychological research so that the center of gravity for the field has swung from the United States to Europe".^[3] Of all nations the United Kingdom has the largest number of active parapsychologists.^[3] In the UK, researchers work in conventional psychology departments, and also do studies in mainstream psychology to "boost their credibility and show that their methods are sound".^[38] It is thought that this approach could account for the relative strength of parapsychology in Britain.^[38]

As of 2007, parapsychology research is represented in some 30 different countries^[3] and a number of universities worldwide continue academic parapsychology programs. Among these are the Koestler Parapsychology Unit at the University of Edinburgh;^[40] the Parapsychology Research Group at Liverpool Hope University (this closed in April 2011);^[41][42] the SOPHIA Project at the University of Arizona;^[43] the Consciousness and Transpersonal Psychology Research Unit of Liverpool John Moores University;^[44] the Center for the Study of Anomalous Psychological Processes at the University of Northampton;^[45] and the Anomalistic Psychology Research Unit at Goldsmiths, University of London.^[46]

Research and professional organizations include the Parapsychological Association;^[47] the Society for Psychical Research, publisher of the Journal of Society for Psychical Research;^[48] the American Society for Psychical Research, publisher of the Journal of the American Society for Psychical Research (last published in 2004);^[49] the Rhine Research Center and Institute for Parapsychology, publisher of the Journal of Parapsychology;^[50] the Parapsychology Foundation, which published the International Journal of Parapsychology (between 1959 to 1968 and 2000–2001)^[51] and the Australian Institute of Parapsychological Research, publisher of the Australian Journal of Parapsychology.^[52] The European Journal of Parapsychology ceased publishing in 2010 ^[53]

Parapsychological research has also been augmented by other sub-disciplines of psychology. These related fields include transpersonal psychology, which studies transcendent or spiritual aspects of the human mind, and Anomalistic psychology, which examines paranormal beliefs and subjective anomalous experiences in traditional psychological terms.^[38][54]

Research[link]

Scope[link]

Parapsychologists study a number of ostensible paranormal phenomena, including but not limited to:

• Telepathy: Transfer of information on thoughts or feelings between individuals by means other than the five classical senses.
• Precognition: Perception of information about future places or events before they occur.
• Clairvoyance: Obtaining information about places or events at remote locations, by means unknown to current science.
• Psychokinesis: The ability of the mind to influence matter, time, space, or energy by means unknown to current science.
• Near-death experiences: An experience reported by a person who nearly died, or who experienced clinical death and then revived.
• Reincarnation: The rebirth of a soul or other non-physical aspect of human consciousness in a new physical body after death.
• Apparitional experiences: Phenomena often attributed to ghosts and encountered in places a deceased individual is thought to have frequented, or in association with the person's former belongings.

The definitions for the terms above may not reflect their mainstream usage, nor the opinions of all parapsychologists and their critics.

According to the Parapsychological Association, parapsychologists do not study all paranormal phenomena, nor are they concerned with astrology, UFOs, Bigfoot, paganism, vampires, alchemy, or witchcraft.^[55]

Methodology[link]

Parapsychologists employ a variety of approaches for the study of apparent paranormal phenomena. These methods include qualitative approaches used in traditional psychology, but also quantitative empirical methodologies.

Experimental research[link]

Ganzfeld[link]

Participant of a Ganzfeld experiment, which proponents say shows evidence of telepathy.

The Ganzfeld (German for "whole field") is a technique used to test individuals for telepathy. The technique—a form of moderate sensory deprivation—was developed to quickly quiet mental "noise" by providing mild, unpatterned stimuli to the visual and auditory senses. The visual sense is usually isolated by creating a soft red glow which is diffused through half ping-pong balls placed over the recipient's eyes. The auditory sense is usually blocked by playing white noise, static, or similar sounds to the recipient. The subject is also seated in a reclined, comfortable position to minimize the sense of touch.^[56]

In the typical Ganzfeld experiment, a "sender" and a "receiver" are isolated.^[57] The receiver is put into the Ganzfeld state^[56] or Ganzfeld effect and the sender is shown a video clip or still picture and asked to mentally send that image to the receiver. The receiver, while in the Ganzfeld, is asked to continuously speak aloud all mental processes, including images, thoughts, and feelings. At the end of the sending period, typically about 20 to 40 minutes in length, the receiver is taken out of the Ganzfeld state and shown four images or videos, one of which is the true target and three of which are non-target decoys. The receiver attempts to select the true target, using perceptions experienced during the Ganzfeld state as clues to what the mentally "sent" image might have been.

Some parapsychologists have claimed that the aggregate results of ganzfeld experiments indicate that, on average, the target image is selected by the receiver more often than would be expected by chance alone; these claims have been summarized by parapsychologist Dean Radin in his book The Conscious Universe.^[56][58] However, the claims are disputed since the interpretation of the aggregate data is unclear;^[8][57] additionally, early Ganzfeld experiments were found to be affected by serious methodological errors. However, the data set post-1985 (which is widely regarded as a turning point in the Ganzfeld experiments) remains statistically significant and has an inclining effect size regression.^[7]

Remote viewing[link]

Remote viewing experiments test the ability to gather information about a remote target consisting of an object, place, or person that is hidden from the physical perception of the viewer and typically separated from the viewer by some distance. In one type of remote viewing experiment, a pool of several hundred photographs are created. One of these is randomly selected by a third party to be the target. It is then set aside in a remote location. The remote viewer attempts to sketch or otherwise describe that remote target photo. This procedure is repeated for a number of different targets. Many ways of analytically evaluating the results of this sort of experiment have been developed. One common method is to take a group of seven target photos and responses, randomly shuffle the targets and responses, and then ask independent judges to rank or match the correct targets with the participant's actual responses. This method assumes that if there were an anomalous transfer of information, the responses should correspond more closely to the correct targets than to the mismatched targets.

Several hundred such trials have been conducted by investigators over the past 25 years, including those by the Princeton Engineering Anomalies Research Laboratory (PEAR) and by scientists at SRI International and Science Applications International Corporation.^[59][60] Many of these were under contract by the U.S. government as part of the espionage program Stargate Project, which terminated in 1995 having failed, in the government's eyes, to document any practical intelligence value.^[61] PEAR closed its doors at the end of February 2007. Its founder, Robert G. Jahn, said of it that, "For 28 years, we’ve done what we wanted to do, and there’s no reason to stay and generate more of the same data."^[62] However, physicist Robert L. Park said of PEAR, "It’s been an embarrassment to science, and I think an embarrassment for Princeton".^[62]

Psychokinesis on random number generators[link]

The advent of powerful and inexpensive electronic and computer technologies has allowed the development of fully automated experiments studying possible interactions between mind and matter. In the most common experiment of this type, a true random number generator (RNG), based on electronic or radioactive noise, produces a data stream that is recorded and analyzed by computer software. A subject attempts to mentally alter the distribution of the random numbers, usually in an experimental design that is functionally equivalent to getting more "heads" than "tails" while flipping a coin. In the RNG experiment, design flexibility can be combined with rigorous controls, while collecting a large amount of data in very short period of time. This technique has been used both to test individuals for psychokinesis and to test the possible influence on RNGs of large groups of people.^[9]

Major meta-analyses of the RNG database have been published every few years since appearing in the journal Foundations of Physics in 1986.^[9] PEAR founder Robert G. Jahn and his colleague Brenda Dunne say that the effect size in all cases was found to be very small, but consistent across time and experimental designs, resulting in an overall statistical significance. The most recent meta-analysis on psychokinesis was published in Psychological Bulletin, along with several critical commentaries.^[63][64] It analyzed the results of 380 studies; the authors reported an overall positive effect size that was statistically significant but very small relative to the sample size and could be explained by publication bias.

Direct mental interactions with living systems[link]

Formerly called bio-PK, "direct mental interactions with living systems" (DMILS) studies the effects of one person's intentions on a distant person's psychophysiological state.^[10] One type of DMILS experiment looks at the commonly reported "feeling of being stared at." The "starer" and the "staree" are isolated in different locations, and the starer is periodically asked to simply gaze at the staree via closed circuit video links. Meanwhile, the staree's nervous system activity is automatically and continuously monitored.

Parapsychologists have interpreted the cumulative data on this and similar DMILS experiments to suggest that one person's attention directed towards a remote, isolated person can significantly activate or calm that person's nervous system. In a meta-analysis of these experiments published in the British Journal of Psychology in 2004, researchers found that there was a small but significant overall DMILS effect. However, the study also found that when a small number of the highest-quality studies from one laboratory were analyzed, the effect size was not significant. The authors concluded that although the existence of some anomaly related to distant intentions cannot be ruled out, there was also a shortage of independent replications and theoretical concepts.^[10]

Near death experiences[link]

Ascent of the Blessed by Hieronymus Bosch (after 1490) depicts a tunnel of light and spiritual figures similar to those reported by near-death experiencers.

A near-death experience (NDE) is an experience reported by a person who nearly died, or who experienced clinical death and then revived. NDEs include one or more of the following experiences: a sense of being dead; an out-of-body experience; a sensation of floating above one's body and seeing the surrounding area; a sense of overwhelming love and peace; a sensation of moving upwards through a tunnel or narrow passageway; meeting deceased relatives or spiritual figures; encountering a being of light, or a light; experiencing a life review; reaching a border or boundary; and a feeling of being returned to the body, often accompanied by reluctance.^[65]

Interest in the NDE was originally spurred by the research of psychiatrists Elisabeth Kübler-Ross, George G. Ritchie, and Raymond Moody. In 1975, Moody wrote the best-selling book Life After Life and in 1977 he wrote a second book, Reflections on Life After Life.^[66] In 1998 Moody was appointed chair in "consciousness studies" at the University of Nevada, Las Vegas. The International Association for Near-death Studies (IANDS) was founded in 1978 to meet the needs of early researchers and experiencers within this field of research. Later researchers, such as psychiatrist Bruce Greyson, psychologist Kenneth Ring, and cardiologist Michael Sabom, introduced the study of near-death experiences to the academic setting.^[65]

Reincarnation research[link]

Jim B. Tucker is Associate Professor of Psychiatry and Neurobehavioral Sciences at the University of Virginia. His main research interests are children who seem to remember previous lives, and prenatal and birth memories.

Psychiatrist Ian Stevenson, from the University of Virginia, investigated many reports of young children who claimed to remember a past life. He conducted more than 2,500 case studies over a period of 40 years and published twelve books, including Where Reincarnation and Biology Intersect and European Cases of the Reincarnation Type.

Stevenson found that childhood memories ostensibly related to reincarnation normally occurred between the ages of three and seven years then fade shortly afterwards. He compared the memories with reports of people known to the deceased, attempting to do so before any contact between the child and the deceased's family had occurred,^[67] and searched for disconfirming evidence that could provide alternative explanations for the reports aside from reincarnation.^[68]

Some 35 per cent of the subjects examined by Stevenson had birthmarks or birth defects. Stevenson believed that the existence of birth marks and deformities on children, when they occurred at the location of fatal wounds in the deceased, provided the best evidence for reincarnation.^[69] However, Stevenson has never claimed that he had proved the existence of reincarnation, and cautiously referred to his cases as being "of the reincarnation type" or "suggestive of reincarnation".^[70] Researchers who believe in the evidence for reincarnation have been unsuccessful in getting the scientific community to consider it a serious possibility.^[71]

Stevenson retired in 2002, and psychiatrist Jim B. Tucker took over his work. Tucker presented an overview of Stevenson's research into reincarnation in Life Before Life: A Scientific Investigation of Children’s Memories of Previous Lives.

Anomalous psychology[link]

A number of surveys have found that many people report having had experiences that could be interpreted as telepathy, precognition, and similar phenomena.^[72][73] Variables that have been associated with reports of psi-phenomena include belief in the reality of psi; the tendency to have hypnotic, dissociative, and other alterations of consciousness; and, less reliably so, neuroticism, extraversion, and openness to experience. Although psi-related experiences can occur in the context of such psychopathologies as psychotic, dissociative, and other disorders, most individuals who endorse a belief in psi generally have normal intellectual functioning and lack serious psychopathology.^[54]

Theory building[link]

Dualism[link]

The psychologists John Raymond Smythies and John Beloff have said non-Cartesian dualism explains psi, in that the mind and brain are separate and that the mind can extend into space to interact with physical matter.^[74] Beloff in his publications has said that the human psyche is an immaterial substance, not dependent for its existence upon the body.^[75]

Bruce Greyson co-author of Irreducible Mind (2007) has presented studies from phenomena such as near-death experiences and mystical experiences to argue for a "strongly dualistic theory of mind and brain".^[76]

Electromagnetic[link]

The electromagnetic theory of psi has been advocated by mostly Soviet scientists who have said that psi may have a physical basis.^[77][78] The Italian neurologist Ferdinando Cazzamali in the 1920s had performed experiments on ESP and claimed that telepathic communication occurred due to a type of electromagnetic radiation.^[79] Most parapsychologists have however rejected the electromagnetic theory as they have said that psi experiments have been successful even when faraday cage barriers were used to screen out electromagnetic radiation. In a response to this some parapsychologists have observed that these results do not rule out all electromagnetic theories of psi as shielding only will rule out familiar forms or wavelengths of radiation. In 1974 Michael Persinger proposed that extremely low frequency (ELF) electromagnetic waves may be able to carry telepathic and clairvoyant information.^[80][81] Persinger and the Soviet scientist I. M. Kogan have said that these extremely low-frequency ELF waves occur in the 300-1000km region and would be able to penetrate electromagnetic shields such as the faraday cages.^[82][83]

Unidentified particles[link]

Some theorists have suggested that an unidentified nonphysical subatomic particle, such as "psitrons", "mindons" or "psychons", carries psi data, responsible for extrasensory perception, telepathy and psychokinesis. Axel Firsoff has said that "mindons" might have properties somewhat similar to those exhibited by neutrinos and may act as a kind of psychic energy.^[84] The psychologist Cyril Burt has said that a "psychon" may exist which would act as a type of "mental field" which may explain some psychic phenomena.^[85] Gerald Feinberg also suggested that telepathy may exist due to as of yet undiscovered elementary particles which he called psychons or mindons.^[86][87]

Feinberg's concept of a tachyon, a theoretical particle that travels faster than the speed of light has been advocated by some parapsychologists who say that it could explain psychokinesis.^[88] The British physicist and mathematician Adrian Dobbs (1965) proposed a theory in which precognition occurs due to “psitrons,” hypothetical particles similar to tachyons that travel backward in time which may contact an observer's brain to produce a precognitive experience.^[89] Hammond (1952) and Ruderfer (1980) have proposed that neutrinos are the possible carrier of psi information.^[90][91]

According to William G. Roll all objects and individuals have "psi fields" around them which are the carriers of psi information.^[92] Ervin László has also supported the "psi field" theory and has attempted to update it with his theory of the "Akashic field". Laszlo has written that this Akashic field is universal and connects everything at the sub-quantum level where it also conserves and conveys all information.^[93][94][95]

Observational theory[link]

Some parapsychologists such as Helmut Schmidt have said the explanation for paranormal phenomena is due to the observational theory of quantum physics.^[96] Some researchers have said that the observer in question could happen to be the "psi source".^[97][98] However the observational theory is not falsifiable.^[99]

Dimensional theories[link]

Other parapsychologists have proposed spacetime models with additional dimensions beyond the usual four in an attempt to explain psi phenomena. Russell Targ, Hal Puthoff and the physicist Elizabeth Rauscher have proposed eight-dimensional models to account for psi phenomena. Rudy Rucker in his book The Fourth Dimension (1984) has reviewed the history of the use of higher-dimensional models to explain psi phenomena. The earliest scientist to propose a dimensional model to explain mediumship was Johann Karl Friedrich Zöllner author of Transcendental Physics (1878).^[100]

Some parapsychologists have said the existence of additional dimensions of time accounts for cases of precognition, déjà vu and synchronicity. John William Dunne in his book An Experiment with Time (1927) had invoked a multidimensional time model with second and third time dimensions. C. D. Broad (1953, 1978) and D. F. Lawden (1982) developed models with two time dimensions.^[101][102] Anthony Peake has built on the theories of Dunne.^[103]

Psychological[link]

Influenced by Carl Jung some parapsychologists have postulated the existence of the collective unconscious in order to explain telepathy and other types of psi phenomena. Some of these theorists, most notably George N. M. Tyrrell (1953) have written that individual minds share common regions at a deep level of the unconscious.^[104] Hans Bender (1980) invoked some of the concepts of Jung to account for certain types of poltergeist phenomena.^[105] In their independent publications Jan Ehrenwald and Jule Eisenbud also advocated psychological theories to explain parapsychology.^[106][107]

Evaluation[link]

Parapsychological theories are currently viewed as pseudoscientific by the scientific community as they are incompatible with well established laws of science,^[108] and parapsychologists have no agreed framework for discussing and testing its claimed phenomena.^[109]

John Beloff in his book Parapsychology: A Concise History (1997) has written that in the Western world parapsychology has been "driven by desire to confound materialism or reductionism" and that there has only been a minority of parapsychologists who have advocated physical theories for psi.^[110] According to the psychical researcher D. Scott Rogo "Unfortunately it is extremely hard for anyone to design a foolproof experiment to prove any one theory of psi."^[111] No accepted theory of parapsychology currently exists, and many competing and often conflicting models have been advocated by different parapsychologists in an attempt to explain reported paranormal phenomena.^[112][113] Terence Hines in his book Pseudoscience and the paranormal (2003) wrote:

Many theories have been proposed by parapsychologists to explain how psi takes place. To skeptics, such theory building seems premature, as the phenomena to be explained by the theories have yet to be demonstrated convincingly.^[114]

According to a report in the Skeptical Inquirer in 1997 no credible theory of psi has yet been presented.^[115] Some parapsychologists such as Dean Radin have said that there is no need to base a theory of psi on physical principles.^[116] The parapsychologist Charles Tart has written that psi is non-physical in basis and does not operate to known physical laws.^[117] Koneru Ramakrishna Rao, a past President of the Parapsychological Association, has written that the lack of any agreed-upon theory of parapsychology is one reason for the general skepticism of the scientific community regarding the existence of paranormal phenomena.^[118] Skeptics such as Antony Flew have cited the lack of such a theory as their reason for rejecting the evidence for psi.^[119]

Criticism and controversy[link]

Questioning the validity of parapsychology research[link]

Fabricated images of ghosts such as this were very popular in the 19th century.

Scientists critical of parapsychology assert that its extraordinary claims demand extraordinary evidence if they are to be taken seriously.^[120] Many analysts of parapsychology hold that the entire body of evidence to date is of poor quality and not adequately controlled. In their view, parapsychology has not produced conclusive results. In support of this view, critics cite instances of fraud, flawed studies, and cognitive biases (such as clustering illusion, availability error, confirmation bias, illusion of control, magical thinking, and the bias blind spot)^[121] as ways to explain parapsychological results.^[122] Skeptics have also contended that people's desire to believe in paranormal phenomena causes them to discount strong evidence that it does not exist.^[123]

The existence of parapsychological phenomena and the scientific validity of parapsychological research is disputed by independent evaluators and researchers. In 1988, the U.S. National Academy of Sciences published a report on the subject that concluded that "no scientific justification from research conducted over a period of 130 years for the existence of parapsychological phenomena."^[124] In the same report, however, they also recommended monitoring some parapsychological research, such as psychokinesis on random number generators and ganzfeld effects, for possible future studies.^[124] The studies at the PEAR lab, recommended for monitoring by the report, have since concluded. These studies likewise failed to elicit a positive response by the scientific community despite numerous trials.^[38] A 2008 study tested participants repeatedly for 90 minutes in a magnetic resonance imaging (fMRI) environment and showed no detectable psi effect, no baseline measure outside of the fMRI was collected for comparison.^[121]

Additionally, the methods of parapsychologists are regarded by critics, including those who wrote the science standards for the California State Board of Education,^[125] to be pseudoscientific.^[126] Some of the more specific criticisms state that parapsychology does not have a clearly defined subject matter, an easily repeatable experiment that can demonstrate a psi effect on demand, nor an underlying theory to explain the paranormal transfer of information.^[127] James E. Alcock, Professor of Psychology at York University ^{[128][129][130][131]} has asserted that few of parapsychology's experimental results have prompted interdisciplinary research with more mainstream sciences such as physics or biology, and that parapsychology remains an isolated science to such an extent that its very legitimacy is questionable,^[132] and as a whole is not justified in being labeled "scientific".^[133] Many in the scientific community consider parapsychology a pseudoscience as they claim it continues to explore the hypothesis that psychic abilities exist despite a century of experimental results that fail to conclusively demonstrate that hypothesis.^[18] Richard Wiseman has criticized the parapsychological community for widespread errors in research methods including cherry-picking new procedures which may produce preferred results, explaining away unsuccessful attempted replications with claims of an "experimenter effect", data mining, and Retrospective data selection.^[134] Whilst Richard Wiseman considers remote viewing to be proven by the current standards of scientific endeavour, he uses this to call for higher standard of evidence when studying the paranormal.^[135]

Carl Sagan has suggested that there are three claims in the field of parapsychology which have at least some experimental support and "deserve serious study", as they "might be true":^[136]

• (1) that by thought alone humans can affect random number generators in computers;
• (2) that people under mild sensory deprivation can receive thoughts or images "projected" at them;
• (3) that young children sometimes report the details of a previous life, which upon checking turn out to be accurate and which they could not have know about in any other way than reincarnation.^[136]

Fraud[link]

Stage magician and skeptic James Randi has stated that magic tricks can simulate or duplicate some supposedly psychic phenomena.

There have been instances of fraud in the history of parapsychology research. The Soal–Goldney experiments of 1941–1943 (suggesting precognitive ability of a single participant) were long regarded as some of the best in the field because they relied upon independent checking and witnesses to prevent fraud. However, many years later, statistical evidence, uncovered and published by other parapsychologists in the field, suggested that Dr. Soal had cheated by altering some of the raw data.^{[132][137][138]}

In 1974, a number of experiments by Walter J. Levy, J. B. Rhine's successor as director of the Institute for Parapsychology, were exposed as fraud.^[139] Levy had reported on a series of successful ESP experiments involving computer-controlled manipulation of non-human subjects, including eggs and rats. His experiments showed very high positive results. Because the subjects were non-human, and because the experimental environment was mostly automated, his successful experiments avoided criticism concerning experimenter effects, and removed the question of the subject's belief as an influence on the outcome.^[140] However, Levy's fellow researchers became suspicious about his methods. They found that Levy interfered with data-recording equipment, manually creating fraudulent strings of positive results. Rhine fired Levy and reported the fraud in a number of articles.^[141][142]

Some instances of fraud amongst spiritualist mediums were exposed by early psychical researchers such as Richard Hodgson^[143] and Harry Price.^[144] In the 1920s, magician and escapologist Harry Houdini said that researchers and observers had not created experimental procedures which absolutely preclude fraud.^[145]

In 1979, magician and debunker James Randi engineered a hoax, now referred to as Project Alpha. Randi recruited two young magicians and sent them undercover to Washington University's McDonnell Laboratory with the specific aim of exposing poor experimental methods and the credulity thought to be common in parapsychology. The McDonnell laboratory did not make any formal statements or publications suggesting that the effects demonstrated by the two magicians were genuine.^[146] However, Randi has stated that both of his recruits deceived experimenters over a period of three years with demonstrations of supposedly psychic abilities: blowing electric fuses sealed in a box, causing a lightweight paper rotor perched atop a needle to turn inside a bell jar, bending metal spoons sealed in a glass bottle, etc.^[147] The hoax by Randi raised ethical concerns in the scientific community, eliciting criticism even among skeptical communities such as the Committee for the Scientific Investigation of Claims of the Paranormal (CSICOP), which he helped found. Psychologist Ray Hyman, a CSICOP member, called the results "counterproductive".^[146]

Criticism of experimental results[link]

Critical analysts, including some parapsychologists, are not satisfied with experimental parapschology studies.^[127][148] Some reviewers, such as psychologist Ray Hyman, contend that apparently successful experimental results in psi research are more likely due to sloppy procedures, poorly trained researchers, or methodological flaws rather than to genuine psi effects.^{[149][150][151][152]} Within parapsychology there are disagreements over the results and methodology as well. For example, the experiments at the PEAR laboratory were criticized in a paper published by the Journal of Parapsychology,^[153] in which parapsychologists independent from the PEAR laboratory concluded that these experiments "depart[ed] from criteria usually expected in formal scientific experimentation" due to "[p]roblems with regard to randomization, statistical baselines, application of statistical models, agent coding of descriptor lists, feedback to percipients, sensory cues, and precautions against cheating." They felt that the originally stated significance values were "meaningless".

A typical measure of psi phenomena is statistical deviation from chance expectation. However, critics point out that statistical deviation is, strictly speaking, only evidence of a statistical anomaly, and the cause of the deviation is not known. Hyman contends that even if psi experiments could be designed that would regularly reproduce similar deviations from chance, they would not necessarily prove psychic functioning.^[154] Critics have coined the term The Psi Assumption to describe "the assumption that any significant departure from the laws of chance in a test of psychic ability is evidence that something anomalous or paranormal has occurred...[in other words] assuming what they should be proving." These critics hold that concluding the existence of psychic phenomena based on chance deviation in inadequately designed experiments is affirming the consequent or begging the question.^[155]

Selection bias and meta-analysis[link]

Selective reporting has been offered by critics as an explanation for the positive results reported by parapsychologists. Selective reporting is sometimes referred to as a "file drawer" problem, which arises when only positive study results are made public, while studies with negative or null results are not made public.^[64] Selective reporting has a compounded effect on meta-analysis, which is a statistical technique that aggregates the results of many studies in order to generate sufficient statistical power to demonstrate a result that the individual studies themselves could not demonstrate at a statistically significant level. For example, a recent meta-analysis combined 380 studies on psychokinesis,^[63] including data from the PEAR lab. It concluded that, although there is a statistically significant overall effect, it is not consistent and relatively few negative studies would cancel it out. Consequently, biased publication of positive results could be the cause.^[38]

The popularity of meta-analysis in parapsychology has been criticized by numerous researchers,^[156] and is often seen as troublesome even within parapsychology itself.^[156] Critics have said that parapsychologists misuse meta-analysis to create the incorrect impression that statistically significant results have been obtained that indicate the existence of psi phenomena.^[157] Physicist Robert Park states that parapsychology's reported positive results are problematic because most such findings are invariably at the margin of statistical significance and that might be explained by a number of confounding effects; Park notes that such marginal results are a typical symptom of pathological science as described by Irving Langmuir.^[25]

Researcher J. E. Kennedy has argued that concerns over the use of meta-analysis in science and medicine apply as well to problems present in parapsychological meta-analysis. As a post-hoc analysis, critics emphasize the opportunity the method presents to produce biased outcomes via the selection of cases chosen for study, methods employed, and other key criteria. Critics say that analogous problems with meta-analysis have been documented in medicine, where it has been shown different investigators performing meta-analyses of the same set of studies have reached contradictory conclusions.^[158]

Skeptics organizations[link]

Organizations that encourage a critical examination of parapsychology and parapsychological research include the Committee for Skeptical Inquiry, publisher of the Skeptical Inquirer;^[159] the James Randi Educational Foundation, founded by illusionist and skeptic James Randi,^[160] and the Occult Investigative Committee of the Society of American Magicians^[161] a society for professional magicians that seeks "the promotion of harmony among magicians, and the opposition of the unnecessary public exposure of magical effects."^[162]

Parapsychologists' rebuttals[link]

Nobel laureate Brian David Josephson is one of the more well-known scientists who say that parapsychological phenomena may be real.

According to some parapsychologists, controversy stems from the apparent elusiveness and unpredictability of parapsychological phenomena and their incompatibility with the established scientific laws. Greater acceptance of the field will therefore be contingent on improved replicability and better integration with related subject areas.^[163]

Harvey J. Irwin and Caroline Watt have discussed "skeptical attacks on parapsychology".^[164] Irwin suggests that skeptics often use name-calling and ridicule to belittle parapsychology, and he says that this approach is characteristic of the Committee for the Scientific Investigation of Claims of the Paranormal and its periodical the Skeptical Inquirer.^[165] Irwin contends that some scientists reject parapsychology simply because they "cannot accept its empirical findings".^[166]

Nobel Laureate Brian David Josephson and some other proponents of parapsychology have spoken of "irrational attacks on parapsychology" which stem from the difficulties of "putting these phenomona into our present system of the universe".^[13] Josephson contends that some scientists feel uncomfortable about ideas such as telepathy and that their emotions sometimes get in the way when making evaluations.^[167] He compares this situation to that of Alfred Wegener's hypothesis of continental drift, where there was initially great resistance to acceptance despite the strength of the evidence. Only after Wegener's death did evidence lead to a gradual change of opinion and ultimate acceptance of his ideas.^[167]

In his 2005 book Life Before Life: A Scientific Investigation of Children's Memories of Previous Lives, Jim B. Tucker acknowledges that some of his main conclusions about reincarnation research may seem to be "astounding" to some readers, but he considers them to be no more astounding than how many currently accepted ideas in physics seemed to be when they were originally proposed.^[168]

There are some aspects of parapsychology which could be interpreted as being characteristic of a "young science".^[169] Proponents of parapsychology have seen it as an "embryo science",^[13] a "frontier science of the mind",^[14] and a "frontier discipline for advancing knowledge".^[15]

Historically, it has been argued that the research agenda pursued by early psychical researchers contributed to the "development of ideas about dissociation and consciousness in mainstream psychology and psychiatry".^[170]

In regard to the issue of fraud, the assertion that parapsychologists have sometimes cheated is undeniable. However, there is no clear evidence that there is an unusually high incidence of fraud in this field.^[171]

Notes[link]