Psi Explorer: Glossary

agent : in telepathy experiments, the sender or transmitter; in spontaneous cases, the person undergoing the experience which will reach the receiver in the form of psi information; in psychokinesis, the person who is the source or catalyst of the PK phenomenon.

altered states of consciousness : states which differ from ordinary waking consciousness, for example, sleep, dreaming, trance, hypnosis, sensory deprivation states, deep relaxation, etc.

anpsi : psi in animals

apparition : the visual manifestation of a deceased person (commonly referred to as a 'ghost') or of a living person, known to be beyond the sensory range of the percipient

astral projection : see out-of-body experience

autoganzfeld : An automated version of the psi ganzfeld experiment created at the Psychophysical Research Laboratories.

bias : the presence of patterns or flaws which cause arbitrary tendencies in data, compromising their validity (example: an unbalanced die with a tendency to favor one number).

blind judge : a person who evaluates or measures experimental results without knowledge of the correct outcome.

chance baseline : the average success rate which is expected if chance alone is operating; often used synonymously with the term 'mean chance expectation'

clairvoyance : knowledge of external objects or events without the use of the physical senses.

control-group : subjects, objects or processes which do not undergo any experimental manipulation and serve as a comparison for groups which have undergone experimental manipulation.

control-test : a procedure which provides an empirical evaluation of chance baseline, or of outcomes in the absence of experimental manipulation.

correlation : a statistical measure of the degree of variation of one parameter in relation to another; in positive correlations, the two factors vary in the same direction; in negative correlations they vary in opposite directions.

decline effect : a tendency towards diminishing results over the course of an experiment or an experimental session.

direct hit : a trial where the subject selects the correct target as their first choice out of a pre-defined number of possibilities.

ESP : extra-sensory perception; knowledge of an external event without the intermediary of any of the known senses. ESP includes the phenomena of telepathy, clairvoyance, and precognition.

experimenter effect : in general, the unintended influence of experimenters upon their experimental results. In parapsychology this effect may be mediated by interpersonal factors, such as their manner of relating to subjects; or it may sometimes involve psi., e.g., unintended telepathic communication of information to subjects.

feedback : in biofeedback sessions, a process whereby a physiological measure (for example, finger temperature) is sent as a visual or audio signal back to the person from whom it is being taken, so that they can learn to control their physiological state. In psi tests, information about the outcome of each trial, provided either in an ongoing fashion, or once the test is finished.

forced-choice procedure : a test in which the subject must try to select the ESP target from a predefined set of known possibilities (e.g., the five symbols of ESP cards).

free-response procedure : a test in which the subject does not know, in advance, the exact nature of the ESP target, and freely describes his/her impressions of it.

Ganzfeld : (German for "uniform or whole field"). A sensory-deprivation protocol for inducing a state of consciousness between wakefulness and sleep; in parapsychology, the ganzfeld is typically used in association with telepathy experiments.

mentation : thoughts, images, or feelings described by the subject during free-response ESP sessions.

metanalysis or meta-analysis : a quantitative method for conducting a review of the literature in a particular domain; generally involves statistical analyses of results obtained across a large number of experiments of the same type.

miss : an incorrect answer in a psi test.

negative psi : tendency of a subject to persistently guess wrong, beyond what would be expected by chance alone; statistically, this means a negative deviation significantly below chance baseline.

out-of-body experience (OBE) : a spontaneous or intentionally induced experience in which the person feels their consciousness to be located elsewhere than where their body is located; in the esoteric literature, referred to as astral projection.

paradigm : a system of scientific interpretation which is embedded in a cultural worldview and implicitly favors certain ways of carrying out and evaluating scientific research.

paranormal : phenomena which seem to go beyond known laws of cause and effect; frequently used as a synonym to parapsychological or psychic.

parapsychology : scientific domain dealing with phenomena which cannot be explained by the known laws of physics or biology; the modern equivalent of psychical research.

PK : see psychokinesis

placebo effect : a cure or alleviation of symptoms following an intervention which the patient believes to be effective against the ailment, but which, in fact, is completely neutral (e.g., a sugar pill). Such effects seem to based on the person's own self-healing capacity, which is triggered by the belief that they are receiving an active medication.

precognition : knowledge of a future event which could not have been predicted or inferred by normal means.

projective psi : psi phenomena which imply an influence of the person on the external world - e.g., as an agent influencing another person's thoughts, in telepathy, or the state of biological or inanimate systems, in PK.

psi : generic term for person-environment interactions which cannot be understood on the basis of known sensory, mechanical or energetic systems. Psi can be both projective (PK) and receptive (ESP).

psi-games : computer psi tests resembling games (e.g., video games).

psychic healing : the healing of one person by another, when this is brought about by purely mental means, i.e., without the use of any known mechanical, chemical or energetic means.

psychokinesis (PK) : mental influence upon an object, a process, or a system, without the use of any known mechanism or energy. PK includes: bio-PK : influencing living systems, whether humans, animals, plants or micro-organisms. macro-PK : directly observable, large-scale influence upon objects. micro-PK : influencing the statistical behavior of random systems, such as dice or electronic noise.

psychometry : the apparent ability of certain psychics to describe the history of a particular object and of people with which it has been in contact simply by holding that object.

receiver : the person who functions as the receptive pole in a psi interaction (i.e., picking up information from another person, in telepathic exchanges).

receptive psi : psi phenomena in which the person receives some information from the environment, or from other people, without the use of any of the known senses. Receptive psi generally refers to ESP, and may include either real-time phenomena (clairvoyance, telepathy) or time-displaced phenomena (precognition, retrocognition).

remote viewing : ESP information identifying a physical location or object at a distance from the receiver. Sometimes used synonymously to clairvoyance, it could actually involve any ESP capacity (telepathy, clairvoyance or precognition.

replication : the reproduction of an experiment (or of other forms of scientific work) by maintaining the same protocol, in order to see if previous results are confirmed or refuted.

replicability : the possibility of reproducing identical or similar results by conducting an experiment of the same type.

Random Number Generator (RNG) : An electronic system which generates true random numbers, based upon a known probabilistic process (such as electronic noise or radioactive decay). RNGs are to be distinguished from Pseudo-RNGs (e.g., the RND function of certain computer languages) which are algorithms simulating truly probabilistic processes.

run : a series of trials in an ESP or PK test, often constituting the unit of statistical measurement ; in an ESP-card test a run consists of 25 trials.

sender : in experiments, the person viewing the target-image which a remotely located receiver is supposed to describe.

sheep-goat effect : a tendency towards divergent psi test scores (sometimes statistically significant ones) according to whether the subjects believe in psi or not: 'goats', who doubt the existence or pertinence of psi, tend tend to score negatively on psi-tests, whereas 'sheep' tend to score positively.

statistical significance : a result is said to be significant when there is no more than a 5% chance that the same result could have been produced by random fluctuations. This is expressed as p = .05

subject : the person who is tested for psi in parapsychological experiments. The term refers to the person considered responsible for any observed psi effects; e.g., in a telepathy experiment, the subject is the receiver, whereas in a 'psychic healing' experiment, it is the one who acts as healer.

subliminal perception : perceptions registered below the threshold of awareness or consciousness.

spiritualism : a quasi-religious popular movement which developed in the 18th and 19th centuries, and which held that the soul survives bodily death, and that the living can communicate with the spirits of the deceased.

target : in ESP, the object or event which the receiver tries to guess (image-targets, card-targets, location-targets, etc.); in PK, the object, process, or system which the subject tries to influence.

telepathy : an exchange of information between two people without any known sensory or energetic interaction.

trial : the experimental unit of a test; for example, in an RNG/computer test, a single click on the button; in an ESP-card test, a single guess of the hidden target-card.

Zener cards : synonymous to ESP cards; a deck of 25 cards made up of 5 different symbols (circle, square, cross, star, waves). Used for telepathy, clairvoyance and precognition experiments.