As in any multidisciplinary domain, there are many ways of conducting research. The five main methods used in parapsychology are:
Although all five of these approaches contribute to the field, today the primary source of "hard evidence" in parapsychology is controlled laboratory experiments. By applying the exacting standards of scientific method, researchers over the past six decades have developed an increasingly persuasive database for certain types of psi phenomena.
Several major experimental designs have been developed during this time, and a select few experiments have now been repeated hundreds of times by dozens of researchers, world-wide. Sometimes these experiments are conducted as strict replications, but more often they are conceptually similar experiments that add controls or extend the range of questions addressed. For a thorough review of how we know that psi experiments are replicable, see The Conscious Universe, a new book by Dean Radin, from HarperCollins Publishers.
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Through popular books and portrayals of parapsychology in movies like Ghostbusters, many people assume that psi experimenters today primarily use the well-known ESP cards. This is a deck of 25 cards, with five repetitions of five cards showing symbols of a square, circle, wavy line, cross, or star. Such cards were developed and used extensively in early psi experiments primarily by J. B. Rhine and his colleagues from the 1930's through the 1960's. ESP cards provided persuasive evidence for ESP, but today they are rarely used by professionals. Four of the most prolific and persuasive of the current experiments are the following:
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The advent of electronic and computer technologies has allowed researchers to develop highly automated experiments studying the interaction between mind and matter. In one such experiment, a Random Number Generator (RNG) based on electronic or radioactive noise produces a data stream that is recorded and analyzed by computer software.
In the typical RNG experiment, a subject attempts to mentally change 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. Of course the electronic, computerized experiment has many advantages over earlier research using, e.g., tossed coins or dice. In the RNG experiment, great flexibility is combined with careful scientific control and a high rate of data acquisition.
A meta-analysis of the database, published in 1989, examined 800 experiments by more than 60 researchers over the preceding 30 years. The effect size was found to be very small, but remarkably consistent, resulting in an overall statistical deviation of approximately 15 standard errors from a chance effect. The probability that the observed effect was actually zero (i.e., no psi) was less than one part in a trillion, verifying that human consciousness can indeed affect the behavior of a random physical system. Furthermore, while experimental quality had significantly increased over time, this was uncorrelated with the effect size, in contradiction to a frequent, but unfounded skeptical criticism.
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This has also been called bio-PK, and more recently some researchers refer to it as Direct Mental Interactions with Living Systems (DMILS). The ability to monitor internal functions of the body, including nervous system activity using EEG and biofeedback technologies, has provided an opportunity to ask whether biological systems may also be affected by intention in a manner similar to PK on RNGs.
A DMILS experiment that has been particularly successful is one that 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. The cumulative database on this and similar DMILS experiments provides strong evidence that one person's attention directed towards a remote, isolated person, can significantly activate or calm that person's nervous system, according to the instructions given to the starer.
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Ganzfeld ("whole field") technique was developed to quiet this external noise by providing a mild, unpatterned sensory field to mask the noise of the outside world. In the typical ganzfeld experiment, the telepathic "sender" and "receiver" are isolated, the receiver is put into the ganzfeld state, 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 report aloud all mental processes, including images, thoughts, feelings. At the end of the sending period, typically about 20 to 40 minutes in length, the receiver is taken out of the ganzfeld, and shown four images or videos, one of which is the true target and three 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. With no telepathy, chance expectation allows us to predict that the correct target would be selected about 1 in 4 times, for a 25% "hit rate." After scores of such experiments, presently totaling about 700 individual sessions conducted by about two dozen investigators, world-wide, the results show that the target image is selected on average 34% of the time. This is a highly significant result, suggesting that telepathy, at least as operationally defined in this experiment, exists.
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The ganzfeld technique indicates that information can be exchanged mentally after the receiver is placed in an altered state of consciousness (the ganzfeld). The remote viewing experiment, in one of its many forms, investigates whether information can be gained without requiring a special altered state, and without a sender. For example, 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, and it is set aside in a remote location. The experimental participant then attempts to sketch or otherwise describe that remote target photo. This is repeated for a total of say, 7 different targets. Many ways of evaluating the results of this test have been developed, including some highly sophisticated methods. One common (and easy) method is to take the group of seven target photos and responses, randomly shuffle the targets and responses, and then ask independent judges to rank order or match the correct targets with the participant's actual responses. If there was real transfer of information, the responses should correspond more closely to the correct targets than to the mismatched targets.
Several thousand such trials have been conducted by dozens of investigators over the past 25 years, involving hundreds of participants. The cumulative database strongly indicates that information about remote photos, actual scenes, and events can be perceived. Some of these experiments have also been used to successfully study precognition by having a participant describe a photo that would be randomly selected in the future.
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Parapsychology uses methods commonly employed in other scientific disciplines. Laboratory studies use research methods from psychology, biology and physics. Field research uses methods from sociology and anthropology. There are plenty of textbooks on research methods in these fields, and we won't attempt to summarize them here.
What's special about parapsychology is the need to pay very close attention to "conventional" explanations. This is because we've defined psi phenomena as exchanges of information that do not involve currently known (i.e., conventional) processes. For instance, we talk about "ESP" when people know about things going on in their environment without getting the information by seeing, hearing, touching, smelling, or through any other known sensory input, or without being able to figure out the "target" information. We talk about "PK" when physical systems appear to react to people's intentions and there's no known physical contact between the person and the "target." Words like "without," and phrases like "no known," show up a great deal in descriptions of psi phenomena.
Therefore, an important part of parapsychological research is eliminating known contact methods from laboratory setups and thinking carefully about them when evaluating reports of people's experiences. In ESP research, this requires knowing about the psychology of sensation, perception, memory, thinking, and communication, and about the biology and physics of sensation and movement. In PK studies, it is important to know about the physical characteristics of the "target," how it works, and what might affect it. In field studies, and in most laboratory studies, it's important to know about the ways in which people can interact with each other. Of course, in field studies it is much more difficult to eliminate conventional explanations than it is in the laboratory because you can't set things up beforehand to eliminate conventional contact between the people and the "targets."
Even when known contact methods are well controlled or eliminated, there is always the possibility that what we observe could have occurred by chance. That is, a person's apparent ESP knowledge about some distant event might be a random guess that just happens to resemble the target. Or, what looks like a PK effect on a physical system might be a random change in that system that just happens to occur at the right time. So it's important to know the statistical methods used to measure how likely it is that the event could have occurred by chance, and how to decide when that's so unlikely that it makes more sense to think there really was some kind of psi contact.
Sometimes field research is not concerned with whether the experiences people report were really psi phenomena, but instead asks questions like, "What do people report about experiences they think were psi?", "How does having these experiences affect their lives?", and "Do people's psychological or cultural characteristics influence how likely they are to interpret experiences as psi?" This is straightforward anthropological, sociological, or psychological research and does not require the same kind of strict attention to eliminating conventional explanations. The value of field research methods is that they investigate the experiences that people actually report. These include experiences such as precognitive dreams, out-of-body experiences, telepathic impressions, auras, memories of previous lives, hauntings and poltergeists and apparitions. Research on these issues results in information about incidence, phenomenology, demographic and psychological correlates of the experiences.
While field or spontaneous case research is less technical, and often more exciting to read, it is wise to avoid jumping to conclusions about the nature of psi from individual cases. Such studies examine how people report or think about their experiences, not what those experiences actually are. However, because spontaneous case studies concentrate on the "raw experience," they offer a valuable view of psi that is often missing in controlled laboratory experiments. Case studies provide a chance to discover the personal meanings and the psychodynamics underlying the experiences, which in turn may provide important hints as to possible mechanisms of psi.
An important goal of laboratory research is to determine the degree to which experiences reported in field and spontaneous-case research can be verified using current scientific methods. If they prove to be verifiable in the lab, the major intent of the lab work usually shifts from "proof-oriented" research to "process-oriented," in which the goal is to discover the psychological, physiological, and physical mechanisms of each phenomenon.
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Constructive criticism is essential in science and is welcomed by the majority of active psi researchers. Strong skepticism is expected, and many parapsychologists are far more skeptical about psi than most scientists realize.
However, it is not generally appreciated that some of the more vocal criticisms about psi are actually "pseudo-criticisms." That is, the more barbed, belligerent criticisms occasionally asserted by some skeptics are often issued from such strongly held, prejudicial positions that the criticisms are not offered as constructive suggestions, but as authoritarian proofs of the impossibility of psi.
It is commonly supposed by non-scientists that skeptical debates over the merits of psi research follow the standards of scholarly discussions. Unfortunately, this is not always the case. Disparaging rhetoric and ad hominem attacks arise too often in debates about psi. The social science of parapsychology, and the way that science treats anomalies in general, is a fascinating topic that starkly illuminates the very human side of how science really works. A more complete description of this topic is beyond the scope of this FAQ, but is contained in the 1997 book, The Conscious Universe, by Dean Radin.
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Criticism: Apparently successful experimental results are actually due to sloppy procedures, poorly trained researchers, methodological flaws, selective reporting, and statistics problems. There is therefore not a shred of scientific evidence for psi phenomena.
Response: These issues have been addressed in detail by meta-analytic reviews of the experimental literature . The results unambiguously demonstrate that successful experiments cannot be explained away by these criticisms. In fact, research by Harvard University specialists in scientific methods showed that the best experimental psi research today is not only conducted according to proper scientific standards, but usually adheres to more rigorous protocols than are found in contemporary research in both the social and physical sciences. In addition, over the years there have been a number of very effective rebuttals of criticisms of individual studies, and within the past decade, experimental procedures have been developed that address virtually all methodological criticisms, even the possibility of fraud and collusion, by including skeptics in the experimental procedures.
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Criticism: Psi phenomena violate basic limiting principles of science, and are therefore impossible.
Response: Twenty years ago, this criticism was a fairly common retort to claims of psi phenomena. Today, with advancements in many scientific disciplines, the scientific worldview is rapidly changing, and the basic limiting principles are constantly being redefined. In addition, the substantial empirical database in parapsychology now presents anomalies that simply won't "go away," thus this criticism is no longer persuasive and is slowly disappearing. Given the rate of change in science today, assigning psi to the realm of the impossible now seems imprudent at best, foolish at worst.
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Criticism: Parapsychology does not have a "repeatable" experiment.
Response: When many people talk about a repeatable psi experiment, they usually have in mind an experiment like those conducted in elementary physics classes to demonstrate the acceleration of gravity, or simple chemical reactions. In such experiments, where there are relatively few, well-known and well-controllable variables, the experiments can be performed by practically anyone, anytime, and they will work. But insisting on this level of repeatability is inappropriate for parapsychology, or for that matter, for most social or behavioral science experiments. Psi experiments usually involve many variables, some of which are poorly understood and difficult or impossible to directly control. Under these circumstances, scientists use statistical arguments to demonstrate "repeatability" instead of the common, but restrictive view that "If it's real, I should be able to do it whenever I want."
Under the assumption that there is no such thing as psi, we would expect that about 5% of well-conducted psi experiments would be declared "successful" (i.e., statistically significant) by pure chance. But suppose that in a series of 100 actual psi experiments we consistently observed that 20 were successful. This is extremely unlikely to occur by chance, suggesting that psi was present in some of those studies. However, it also means that in any particular experiment, there is an 80% probability of "failure." Thus, if a critic set out to repeat a psi experiment to see if the phenomenon was "real," and the experiment failed, it would obviously be incorrect to claim on the basis of that single experiment that psi is not real because it is not repeatable.
A widely accepted method of assessing repeatability in experiments is called meta-analysis. This quantitative technique is heavily used in the social, behavioral and medical sciences to integrate research results of numerous independent experiments. Starting around 1985, meta-analyses have been conducted on numerous types of psi experiments. In many of these analyses, results indicate that the outcomes were not due to chance, or methodological flaws, or selective reporting practices, or any other plausible "normal" explanations. What remains is psi, and in several experimental realms, it has clearly been replicated by independent investigators.
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Version: July 24, 1997
Copyright 1995, 1996, 1997 by Dean Radin