Ganzfeld experiment
A ganzfeld experiment (from the German words for "entire" and "field") is an assessment used by parapsychologists that they contend can test for extrasensory perception (ESP) or telepathy.
The receiver is normally asked to choose between a limited number of options for what the transmission was supposed to be and parapsychologists who propose that such telepathy is possible argue that rates of success above the expectation from randomness are evidence for ESP.
Consistent, independent replication of ganzfeld experiments has not been achieved, and, in spite of strenuous arguments by parapsychologists to the contrary, there is no validated evidence accepted by the wider scientific community for the existence of any parapsychological phenomena.
[6] In the early 1970s, Charles Honorton at the Maimonides Medical Center was trying to follow in the footsteps of psychical researchers such as Joseph Banks Rhine who had coined the term "ESP" to elevate the discourse around paranormal claims.
Honorton focused on what he thought was the connection between ESP and dreams and began exposing his research subjects to the same sort of sensory deprivation that is used in demonstrations of the ganzfeld effect, hypothesizing that it was under such conditions that "psi" (a catch-all term used in parapsychology to denote anomalous psychic abilities) might work.
[7] Honorton believed that by reducing the ordinary sensory input, "psi-conductive states" would be enhanced and "psi-mediated information" could be more effectively transmitted.
In a typical Ganzfeld experiment, a "receiver" is placed in a room relaxing in a comfortable chair with halved ping-pong balls over the eyes, having a red light shone on them.
Once time expires, the receiver is taken out of the Ganzfeld state and shown a set of possible targets, from which they select one which most resembles the images they witnessed.
After considerable back-and-forth over the relevance and importance of the flaws, Honorton came to agree with Hyman the 42 ganzfeld experiments he had included in his 1982 meta-analysis could not in themselves support the claim for the existence of psi.
[22] He expressed concerns with the randomization procedure, the reliability of which he was not able to confirm based on the data provided by Honorton's collaborator, Daryl Bem.
[17]Hyman wrote these studies were an improvement over their older counterparts, but were not a successful replication of the ganzfeld experiments, nor a confirmation of psi.
[17] Richard Wiseman published a paper discussing a non-psi hypothesis based on possible sender to experimenter acoustic leakage in the autoganzfeld to account for the results.
[26] In response, Milton and Wiseman (2001) wrote the meta-analysis of Storm and Ertel was not an accurate quantitative summary of ganzfeld research as they had included early studies which had been widely recognized as having methodological problems which make it impossible to interpret the results as evidence of a psi effect.
[10] Hyman (2010) published a rebuttal to Storm et al. concluding that the ganzfeld studies have not been independently replicated and had thus failed to produce evidence for psi.
[30] According to Hyman, "reliance on meta-analysis as the sole basis for justifying the claim that an anomaly exists and that the evidence for it is consistent and replicable is fallacious.
Storm et al. published a response to Hyman claiming the ganzfeld experimental design has proved to be consistent and reliable but parapsychology is a struggling discipline that has not received much attention so further research on the subject is necessary.
"[36] David Marks in his book The Psychology of the Psychic (2000) has noted that during the autoganzfeld experiments the experimenter sat only fourteen feet from the sender's room.
[37] In a 2007 review, Ray Hyman wrote that parapsychologists agree they have no positive theory of psi as it is negatively defined as any effect that cannot be currently explained in terms of chance or normal causes.
Indeed given the obvious instability and elusiveness of the findings, the best guess might very well be that we are dealing with a variety of Murphy's Law rather than a revolutionary anomaly called psi.In their book 50 Great Myths of Popular Psychology (2011), Scott O. Lilienfeld and colleagues have written that the ganzfeld being a reliable technique is far from being resolved.
Psychologists reading Daryl Bem's review in Psychological Bulletin would "not have a clue that serious doubt had been cast on more than a quarter of the studies involved".
Blackmore also recounts having a discussion with Bem at a consciousness conference where she challenged him on his support of Sargent and Honorton's research, he replied "it did not matter".
