Scientific investigation of telepathy

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Numerous scientific experiments seeking evidence of telepathy have been conducted over more than a century. Many of these studies have yielded positive results, most notably using the Ganzfield procedure. However, telepathy, as with all parapsychological subjects, remains controversial.

[edit] Early investigations

Western scientific investigation of telepathy is generally recognized as having begun with the initial program or research of the Society for Psychical Research. The apex of their early investigations was the report published in 1886 as the two-volume work Phantasms of the Living. It was with this work that the term "telepathy" was introduced, replacing the earlier term "thought transference". Although much of the initial investigations consisted largely of gathering anecdotal accounts with follow-up investigations, they also conducted experiments with some of those who claimed telepathic abilities.[citation needed] However, their experimental protocols were far more lax than those used today.[citation needed]

In 1917, psychologist John E. Coover from Stanford University conducted a series of telepathy tests involving transmitting/guessing playing cards. His participants were able to guess the identity of cards with overall odds against chance of 160 to 1;[citation needed] however, Coover did not consider the results to be significant enough to report this as a positive result.[citation needed]

The best-known early telepathy experiments were those of J. B. Rhine and his associates at Duke University, beginning in the 1927 using the distinctive ESP Cards of Karl Zener (see also Zener Cards). These involved more rigorous and systematic experimental protocols than those from the 19th century, used what were assumed to be 'average' participants rather than those who claimed exceptional ability, and used new developments in the field of statistics to evaluate results. Results of these and other experiments were published by Rhine in his popular book Extra Sensory Perception, which popularized the term.

Another influential book about telepathy was Mental Radio, published in 1930 by the Pulitzer prize-winning author Upton Sinclair (with foreword by Albert Einstein). In it Sinclair describes the apparent ability of his wife at times to reproduce sketches made by himself and others, even when separated by several miles. They note in their book that the results could also be described by the more general term clairvoyance, and they did some experiments whose results suggested that in fact no sender was necessary, and some drawings could be reproduced precognitively.[citation needed]

By the 1960s, many parapsychologists had become dissatisfied with the forced-choice experiments of J. B. Rhine, partly because of boredom on the part of test participants after many repetitions of monotonous card-guessing,[citation needed] and partly because of the observed "decline effect" where the accuracy of card guessing would decrease over time for a given participant, which some parapsychologists attributed to this boredom.[citation needed]

Some parapsychologists turned to free response experimental formats where the target was not limited to a small finite predetermined set of responses (e.g., Zener cards), but rather could be any sort of picture, drawing, photograph, movie clip, piece of music etc.[citation needed]

[edit] Notable experiments

The following is a list of some notable experiments done on telepathy in modern history.

[edit] Zener card experiments

Zener cards
Zener cards

Dates run: 1930's

Experimental philosophy: A Zener Card deck is created, which consists of five cards each of five different symbols. The deck is shuffled, and the subject is asked to guess the identity of each card as it is drawn and viewed by a sender. In this experiment, telepathy is assumed to be weak, and only expected to give a small deviation towards correct answers.[citation needed]

Experimental design: J. B. Rhine, the experimenter, would sit across a table from the subject. He would shuffle the Zener Card deck, and draw cards one at a time. For each card, he would look at it and ask the psychic to guess its identity by reading his mind. A hit rate of significantly more or less than 20% was considered to be evidence of telepathy. Hit rates significantly below 20% were reguarded psi-missing, the phenomenon in which psi may cause missing due to the attitude of the experimenter or subject toward the situation or subject matter.[1]

Results: Rhine's studies produced results which were significantly above or below chance in a statistical sense.[2] He noted, however, that this experiment couldn't adequately distinguish telepathy from clairvoyance.[3]

[edit] Ganzfeld experiments

(Main article: Ganzfeld)

Dates run: 1974 to present

Experimental philosophy: The subject is placed in sensory deprivation, in hopes that this will make it easier to receive and notice incoming telepathic signals. In this experiment, telepathy is assumed to be weak, and only expected to give a small deviation towards correct answers.[4]

Experimental design: The receiver (a possible psychic, who is being tested) is placed in a soundproof room and sits reclining in a comfortable chair. The subject wears headphones which play continuous white noise or pink noise. Halves of ping pong balls are placed over their eyes, and a red light is shined onto the subject's face. These conditions are designed to cause the receiver to enter a state similar to being in a sensory deprivation chamber.

The sender is seated in another soundproof room, and is assigned one of four potential targets, randomly selected. Typically, these targets are pictures or video clips. The sender attempts to telepathically "send" information about the target to the receiver. The receiver is generally asked to speak throughout the sending process, and their voice is piped to the sender and experimenter. This is to assist the sender in determining if their method of "sending" information about the target is working, and adjust it if necessary. Breaks may be taken, and the sending process may be repeated multiple times.

Once the sending process is complete, the experimenter removes the receiver from isolation. The receiver is then shown the four potential targets, and asked to choose which one they believe the sender saw. In order to avoid potential confounding factors, the experimenter must remain ignorant of which target was chosen until the receiver makes their choice, and multiple sets of the pictures of videos should be used in order to avoid handling cues (evidence, such smudges on a picture, that the picture was handled by the sender).[citation needed]

A statistical analysis is performed to find out whether the subject scored significantly above or below chance.[5]

Results: Many meta-analyses performed on multiple Ganzfeld experiments returned a hit rate of between 30% and 40%, which is significantly higher than the 25% expected by chance.[6][7]

[edit] Criticism

The following are common criticisms of some or all of the Ganzfeld experiments:

Isolation - Not all of the studies used soundproof rooms, so it is possible that when videos were playing, the experimenter (or even the receiver) could have heard it, and later given involuntary cues to the receiver during the selection process.[8] However, ganzfeld studies which did use soundproof rooms had a number of "hits" similar to those which did not.[2] (Radin 1997: 77-89)

Handling cues - Only 36% of the studies performed used duplicate images or videos, so handling cues on the images or degradation of the videos may have occurred during the sending process.[9] However, the results of studies were not found to correspond to this flaw.

Randomization - When subjects are asked to choose from a variety of selections, there is an inherent bias to not choose the first selection they are shown. If the order in which are shown the selections is randomized each time, this bias will be averaged out. However, this was often not done in the Ganzfeld experiments.[10][11]

The psi assumption - The assumption that any statistical deviation from chance is evidence for telepathy is highly controversial, and often compared to the God of the gaps argument. Strictly speaking, a deviation from chance is only evidence that either this was a rare, statistically unlikely occurrence that happened by chance, or something was causing a deviation from chance. Flaws in the experimental design are a common cause of this, and so the assumption that it must be telepathy is fallacious. This does not rule out, however, that it could be telepathy.[12]

Parapsychologists respond, however that while there are many potential theoretical explanations of psi, parapsychology as a science does not claim to understand what psi is, but

Instead, [parapsychologists] design experiments to test experiences that people have reported throughout history. If rigorous tests for what we have called [say] "telepathy" result in effects that look like, sound like, and feel like the [often more impressive [13]] experiences reported in real life, then call it what you will, but the experiments confirm that this common experience is not an illusion.[2] (Radin 1997: 210)

"Psi" is the name for an unknown factor, not necessarily for a force or factor outside the current range of scientific knowledge.

[edit] Controversy

The existence of telepathy is still a matter of extreme controversy, with many skeptics stating that evidence for it does not exist. A scientific methodology which always shows statistically significant evidence of telepathy has yet to be discovered. Skeptics argue that the lack of a definitive experiment whose reproducibility is near 100% (e.g. those which exist for magnetism) may indicate that there is no credible scientific evidence for the existence of telepathy. Skeptics also point to historical cases in which flaws have been discovered in the experimental design of parapsychological studies, and the occasional cases of fraud which have marred the field.[14][15] Those who believe that telepathy may exist say that very few experiments in psychology, biology, or medicine can be reproduced at will with consistent results. Parapsychologists such as Dean Radin argue that the extremely positive results from reputable studies, when analyzed using meta-analysis, provide strong evidence for telepathy that is almost impossible to account for using any other means[2].

[edit] Fraud

Some critics say that some positive results of parapsychological experiments, where they are not due to design flaws, may be due to deliberate fraud.

There are at least half a dozen peer-reviewed journals of parapsychology. However, research in this area has been characterized by deception, fraud, and incompetence in setting up properly controlled experiments and evaluating statistical data (Alcock 1990; Gardner 1981; Gordon 1987; Hansel 1989; Hines 1990; Hyman 1989; Park 2000; Randi 1982)."[16]

Some parapsychological studies have been badly designed, in such a way as to permit fraud. In the case of Project Alpha, magician James Randi planted magicians as subjects of a parapsychological experiment, and they were able to fool the researchers over a prolonged period.[17] Such methodological failures have been cited by skeptics as evidence of the probability that many parapsychological results derive from error or fraud.[citation needed]

[edit] See also

[edit] References

  1. ^ http://www.parapsych.org/sheep_goat_effect.htm The Sheep - Goat Effect by Mario Varvoglis, Ph.D., from the website of the Parapsychological Association, retrieved December 27, 2006
  2. ^ a b c d The Conscious Universe: The Scientific Truth of Psychic Phenomena by Dean I. Radin Harper Edge, ISBN 0-06-251502-0
  3. ^ Randi, James (1995). An Encyclopedia of Claims, Frauds, and Hoaxes of the Occult and Supernatural. St. Martin's Press. ISBN 0-312-15119-5. 
  4. ^ Bem, Daryl J. and Honorton, Charles (1994). Does Psi Exist?. Psychological Bulletin, Vol. 115, No. 1, 4-18. Retrieved on June 23, 2006.
  5. ^ ibid
  6. ^ ibid
  7. ^ Hyman, Ray (March/April, 1996). The Evidence for Psychic Functioning: Claims vs. Reality. Skeptical Inquirer. Retrieved on June 23, 2006.
  8. ^ Wiseman, R., Smith, M,. Kornrot, D. (June 1996). Exploring possible sender-to-experimenter acoustic leakage in the PRL autoganzfeld experiments. Journal of Parapsychology.
  9. ^ Carpenter, S. (July 31, 1999). ESP findings send controversial message. Science News. Retrieved on June 23, 2006.
  10. ^ Hyman, Ray (1985). "The ganzfeld psi experiment: A critical appraisal". Journal of Parapsychology (49): 3-49. 
  11. ^ Honorton, C (1985). "Meta-analysis of psi ganzfeld research: A response to Hyman". Journal of Parapsychology (49): 51-91. 
  12. ^ Carroll, Robert Todd (2005). The Skeptic's Dictionary: Psi Assumption. Retrieved on June 23, 2006.
  13. ^ http://twm.co.nz/FAQpara2.htm#9.5 Parapsychology FAQ, Compiled by Dean Radin, PhD of UNLV's Cognitive Research Division A helpful guide to parapsychology and the facts regarding that field, Retrieved December 26, 2006
  14. ^ Carroll, Robert Todd (2005). The Skeptic's Dictionary; ESP (extrasensory perception). SkepDic.com. Retrieved on September 13, 2006.
  15. ^ "Most academic psychologists do not yet accept the existence of psi..." Bem, Daryl J. and Honorton, Charles (1994). Does Psi Exist?. Psychological Bulletin, Vol. 115, No. 1, 4-18. Retrieved on September 13, 2006.
  16. ^ http://skepdic.com/parapsy.html Skeptics Dictionary on Parapsychology
  17. ^ http://www.banachek.org/nonflash/project_alpha.htm Project Alpha, The Skeptical Inquirer Summer 1983 The Project Alpha Experiment: Part one. The First Two Years by James Randi

[edit] Further reading

  • Hansel, C.E.M. (1989), The Search for Psychic Power: ESP & Parapsychology Revisited, Prometheus Books, ISBN 0-87975-533-4