Supersensory perception: between faith and science

Telepathy, clairvoyance and other psychic abilities: despite many studies in this field, such abilities have rarely been demonstrated in well-controlled experiments

Supersensory perception - what is it?

The term "Extrasensory Perception" (Extrasensory Perception), abbreviated as ESP, refers to a wide variety of phenomena whose existence is disputed, which are supposed to manifest in the ability of people with special skills (and some claim that to one degree or another of all - the person) to receive information about the world other than through the familiar senses. The field of OT research is called parapsychology, and the main phenomena it deals with are:

 Telepathy - the ability (so to speak) to "read" the other person's thoughts or to know what is in their mind: intentions, memories, mental images, and the like.
Clear vision (clairvoyance) or remote viewing (remote viewing) - the ability (so to speak) to know about what is happening outside the range of the senses without an intermediary (and not through telepathy).
Foresight (precognition) - the ability (so to speak) to anticipate the future without using the usual deduction processes.
Telekinesis (telekinesis) or psychokinesis (psychokinesis) - the ability (so to speak) to move objects or influence the physical environment in some way through thought alone (the expression of this phenomenon is indeed an action and not a perception, but it is traditionally associated with this category).

 Periodic surveys reveal that a large percentage of the population, including part of the educated population, believe that these phenomena do exist, and many even believe that their existence has been scientifically proven. The mass media undoubtedly contribute to this belief, including popular magazines, which spread unreliable information, whether in good faith or out of a desire to attract viewers and readers. Below we will review the scientific position on the subject, which as usual takes a cautious and skeptical approach when it comes to unusual phenomena.

Studies: the beginning

Anecdotes about people with psychic abilities, and about "ordinary" people who experienced events that could be interpreted as psychic experiences, have probably been told since time immemorial, but systematic scientific research on the subject only began in 1882, with the establishment in Great Britain of the Society for Psychic Research (The Society for Psychical Research). The first experiment on behalf of the company was to test the telepathic ability of the Creery sisters, the five daughters of a British clergyman, who claimed such an ability. William Fletcher Barrett, a physics professor from Dublin, who conducted the experiment, was convinced of their telepathic ability. A few years later, the sisters admitted that they had cheated in the experiment, and even explained how they did it (using simple verbal codes, a technique now known to every beginning magician).

In another experiment at the beginning of the company, the telepathic ability of George Albert Smith (Smith) and his colleague Douglas Blackburn (Blackburn), who used to present their "abilities" in public shows, was tested. The researchers were convinced of their ability to "read minds" and saw this as proof of the existence of supernatural phenomena. Blackburn later admitted (although Smith denied) that the two had cheated on the experiment. The fact that the first experiments conducted on the topic of paranormal perception were presented as an impressive success, and that later it turned out that the subjects used "tricks", can be considered in retrospect as a hint of things to come, since over the years a considerable number of people who claimed special abilities managed to fool the researchers. Some of them confessed after the fact that they had cheated, and many others were caught red-handed.

 One of the pioneers of parapsychological research was Joseph Banks Rhine (Rhine) from Duke University, who conducted many experiments in the field in the 20s and 25s, and he also coined the term parasensory perception. Raine assumed that extrasensory abilities might be expressed to one degree or another in the general population, and therefore based his experiments on statistical methods. In many of the experiments Raine used decks of XNUMX Zener cards, cards decorated with one of five simple drawings: a circle, a cross, waves, a square and a five-pointed star.

In these experiments, which are still accepted today, the experimenter draws one card from the deck at a time, and the subject must guess which card was drawn. Assuming that without additional information the chance of correctly guessing each of the cards is 1:5, then by means of statistical calculations it is possible to determine what the probability is that any series of guesses will be random.

 Raine's assumption was that any significant deviation from the statistically expected number of correct guesses is a manifestation of some kind of psychic ability: if the experimenter observes the cards as he draws them, then a large number of hits suggests a telepathic ability; If the subject guesses correctly even before the experimenter looks at the card, it is clear vision; And if there is a high correlation between the subject's guess and the next card that will be drawn from the deck, then this is evidence of foresight.

 Rein published many studies that supposedly indicated positive findings in his experiments, but over the years the scientific community's criticism of these studies increased. A careful examination revealed serious flaws in them: some of the subjects admitted in retrospect that they had cheated; It turned out that some of Raine's assistants had altered the results of experiments to obtain statistical significance; In the first experiments, the lighting conditions made it possible to see the shapes appearing on the cards from the other side as well, and in general the experimenter and the subject sat close enough to each other to allow information leakage; The subjects sometimes had access to the cards themselves, either during the experiment or before it; The order in the decks was not always random, and they were not always shuffled properly for reuse; And finally, it turned out that some of the statistical methods that were used did not fit the experimental setups.

 When the experimental setups were changed in a way that reduces the chance of cheating and leaking information, and when more appropriate statistical methods were put into use, the significance of the results disappeared or was significantly reduced. Rein's interpretations of the results were also sharply criticized, since when the results of the experiments were particularly low (a phenomenon called "psychic absence"), Rein interpreted this as a psychological resistance of the subjects to the experiment, and when subjects obtained good results at the beginning of the experiment, but the results weakened later in the experiment (parapsychologists call This is the "weakening result"), Rein saw it as an expression of boredom or loss of concentration, when in fact it is a simple statistical phenomenon called "regression to the mean".

Studies today

Since Rain's experiments, much water has flowed in parapsychological research. Most of the publications on the subject appeared in pseudo-scientific journals and received cold criticism from the scientific community, with an emphasis on faulty experimental setups that leave an option for cheating, on flawed statistical methods, and above all - on the lack of flatness: the positive results obtained in a certain laboratory disappeared as if they were not there when they tried to reproduce them in other laboratories in the world. Some researchers, such as Susan Blackmore, gave up after years of well-controlled experiments that did not produce results, and became critics of parapsychological research, but many others still hope to obtain results that will bring about a change in science's perception of the world. Despite the general agreement of the researchers that there is a real difficulty in obtaining positive results and the frequency of well-controlled parapsychological experiments, many of them hang their gold on one type of experiment, which they believe is the great hope of parapsychological research: the Ganzfeld experiments.

 The Ganzfeld experiment (Ganzfeld, "complete field" in German) is based on the assumption that the strength of the supersensory information accessible to us is extremely low, and this information is lost against the background of the constant sensory stimuli. Therefore, isolating the subject from sensory stimuli may increase his accessibility to information, and give expression to his supersensory abilities. For this purpose, the subject is placed in an isolated and sound-proof room, his eyes are covered with halves of ping-pong balls illuminated with red light, and headphones are placed on his ears that play white noise (a noise of equal intensity at all audio frequencies, roughly like the sound of heavy rain). In another isolated room sits a person, who looks at a certain image and tries to "broadcast" it in his mind to the subject, while the subject reports every image that comes to mind. After that, the experimenter shows the subject several pictures, only one of which is the picture that was "broadcast" to him, and the subject must rate these pictures according to how well they match the pictures that came to mind during the experiment.

 In 1994, the psychologist Daryl Bem (Bem) from Cornell University and the parapsychologist Charles Honorton (Honorton) from the University of Edinburgh published in the respected psychological journal "Psychological Bulletin" a meta-analysis of 11 Ganzfeld experiments (a meta-analysis is a statistical analysis of several independent experiments , sometimes the work of different researchers. It is possible that in some of these experiments the results were not statistically significant, but when you take them all into account, significance may be revealed). Bem and Honorton's conclusion from the overall statistical analysis of these experiments was that they indicate a certain psychic ability among the subjects. The researchers also claimed that they discovered a correlation between paranormal ability and certain characteristics of the subjects, including: artistic creativity, extroversion, previous experiences with paranormal perception and engaging in some mental technique (for example, meditation).

 This study raised great hopes in parapsychological research, but in 1999, Julie Milton (Milton) of the University of Edinburgh and Richard Wiseman (Wiseman) of the University of Hertfordshire, again in the "Psychological Bulletin", published a meta-analysis of 30 Ganzfeld experiments that were not included in the study of Bem and Honorton. The findings of this study do not support the existence of any kind of supersensory perception (which again emphasizes the infrequency with which research in the field is flawed). Milton Weissman also rejected some of the conclusions of Bem and Honorton's research, including the correlation that was supposedly discovered between some of the subjects' characteristics and the psychic ability as manifested in their research.

 Several parapsychological studies were also conducted under the auspices of various governments in the world, who wanted to evaluate the military applications of psychic abilities, if indeed they really exist. Despite the popular stories about armies using mediums as spies, there is no evidence of any success of these experiments, and most projects have been discontinued at one point or another. Such an American project, called "Stargate", was analyzed through a meta-analysis by Jessica Utts (Utts), a professor of statistics from the University of California, and according to her, extrasensory perception, including remote vision, was demonstrated in the project's experiments.

 However, Ray Hyman, a psychologist from the University of Oregon, who has been involved in the evaluation of research in parapsychology for many years, also analyzed the results of the project and reached other conclusions, and even pointed out flaws in Oates' research. Among other things, Heiman pointed out one of the problems in meta-analysis, which is particularly relevant to this field of research, and is the tendency not to publish experiments that produced negative results. If the unpublished ones were also added to the list of experiments analyzed in the meta-analysis, the significance of the results would probably decrease significantly.

 In general, research in parapsychology is characterized by several recurring problems: the lack of apartments. Since mistakes may occur in an experiment, and many cases of cheating and falsification of results are known (even among the scientific community), science is ready to adopt only the results of experiments conducted by several independent groups of researchers. To date, parapsychological research has not provided even one type of experiment that can be repeated over and over again to demonstrate any kind of paranormal ability.
cheating In parapsychological research, more than in any other scientific research field, fraudulent acts of the subjects and sometimes also of the researchers have been discovered. Therefore, any experimental set-up that leaves an opening for obtaining the required information by normal (and not supersensory) means is not admissible. Despite this, many experiments conducted in the field fail to completely prevent the possibility of cheating. Furthermore, when in experiments where positive results were obtained, the experimental set-up is adjusted in a way that reduces the chance of cheating, the positive results miraculously disappear (but there are also parapsychologists who claim that the reason for this is that extrasensory perception is an unstable ability, it ceases to manifest itself when it is doubted. This is Also the reason, according to them, is that when such experiments are conducted by skeptical scientists, the subjects fail to demonstrate extrasensory ability - a phenomenon they call "the experimenter's result" or "the result of shyness").
Poor documentation. Many of the experiments are not properly documented, and this makes it difficult for other researchers to assess the quality of the experiments and find flaws in them.
statistical bias. Statistics allow and even require that some experiments have high concentrations of shots (even when a coin is tossed a large number of times, here and there you get long sequences of "flies" or "trees"). Quite a number of experiments, which start with a sequence of correct guesses, are stopped at an early stage and announced as positive results. In contrast, experiments that start with a relatively small number of shots are sometimes stopped and are not reported. Furthermore, some of the experiments are preceded by a "warm-up" phase, and in the absence of a protocol that defines the length of the "warm-up", there is sometimes a tendency to start the experiment itself when a long sequence of shots is obtained, which guarantees better results. 
Flaws in statistical analyses, such as the use of assumptions that correspond to an infinite number of guesses, even though in each experiment the number of guesses is of course finite, as well as the assumption of randomness even when inappropriate procedures are taken to obtain randomness (for example, in arranging the cards), which sometimes increases the chance of obtaining positive results.

 Indeed, a careful examination of experiments in parapsychological research reveals a high correlation between experiments that produced positive results and experiments that were found to have one or more of the above problems.

Summary

The debate over whether paranormal ability has ever been demonstrated in a parapsychological experiment is still ongoing. Most of the researchers who are convinced of the existence of these abilities work outside the scientific community, and publish mainly in non-scientific journals. In contrast, many researchers within the scientific community repeat and point out the flaws in these experiments and their irregularity, as well as the lack of a theory to explain such abilities. The fact that after over a hundred years of research, no paranormal phenomenon has yet been convincingly and rarely demonstrated, and even the results of Ganzfeld's experiments, which are considered the most promising in parapsychological research, are questionable, raises a big question mark regarding the very existence of paranormal perception.