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Displacement is a psiological phenomenon that defines a statistical or qualitative correspondence between a stimulus and a set of responses that occurs independently of their normally perceptible spatial and temporal relationships. The term implies that what is given as a report of present mental data betrays perception of information that is external to the focus of presently intended attention. Instead of the intended object of perception, what is reported is something that is yet to occur, has occurred in the past, or only occurs in a spatially unattended context.

Experimental identification of the effect

Early psychical researchers, in the late 1800s, often identified that their participants reported information that qualitatively appeared to be related to alternative targets, equally shielded from sensory perception as the target assigned to a trial. For example, if there were two targets - firstly, a picture of an anvil, and then a picture of a ladle - to be drawn, one after the other, by the participant, but the participant first drew a ladle, then it might be suspected that the participant had indeed been informed by one of the targets, but not on the trial to which it was assigned. With the introduction during the 1930s by J. B. Rhine of a standard method of testing for extrasensory perception that yielded quantitative data, more sensitive and objective measures of this supposed effect could be made. The method involved participants in matching a set of symbols (printed on cards) with a randomly ordered and concealed target set of the same symbols; a forced-choice matching procedure. Displacement could be studied with this method by scoring the matches between the two sets when one set was shifted one or more trials ahead or behind the other.

The first report of displacement, with this method, appeared in 1938. This was anonymously authored by then Secretary of the Smithsonian Institution, astrophysicist Charles Greeley Abbot. He observed that his guesses for the identity of cards shielded to his sensory perception were reliably accurate - beyond the chance-level predicted by probability theory - not only when scored for target-response identities, but also when the responses were tallied for targets one removed, by trial, from those for which they were assigned.

Two years later, an article appeared in the journal Nature that announced independent discovery of the effect. This article was authored by British researchers, Whately Carington and Samuel Soal. Carington described how, in his studies of the "paranormal cognition of drawings", statistically significant correspondences between targets and responses occurred not only for assigned targets, but for targets temporally contiguous with them. Soal reported the same effect occurring within the data of two participants in his card-guessing experiments. The British psychologist Robert H. Thouless reported confirmatory observations in a 1942 article published in the British Journal of Psychology. Following his retirement from the Smithsonian in 1944, Abbot undertook further study of displacement, replicating the effect, and openly claiming authorship of his previous report.

Importantly for the statistical validity of the displacement effect, all of these early researchers reported statistically significant displacement while taking the total tested range of stimulus-response correspondences into account. In this way, identifying significant displacement can not be attributed to multiple analysis of the same data. There has, however, been continuing concern as to the statistical independence of the displacement effect from scores for assigned targets. Various statistical approaches to the question have been proposed, including by the leading statisticians Bartlett and Greville. From among these approaches, the most appropriate approach for a particular test situation depends on a number of factors, including the manner in which the target series has been sampled, whether or not the assigned target was correctly responded to, and the number of trials being measured for displacement scores.

Varieties of the effect

From the 1930s, terminology concerning the displacement effect has become increasingly more precise. Following Thouless' definitions, the parapsychological literature generally denotes a displacement where a response is equivalent to the target for the next trial as a (+1) displacement. Where the response corresponds to the prior trial, the convention is to refer to a (-1) displacement. Higher order displacements have not often been studied, given early computational limits, and the increased number of hypotheses that the data are asked to support. Ongoing technological and statistical developments have permitted deeper analysis of the effect, over larger trial-shifts between targets and responses.

During the 1940s and 1950s, the relationship of displacement to other properties of forced-choice matching became of interest, particularly for then Duke University psychologist J. G. Pratt. A key question was if the accuracy of displaced scoring was related to the accuracy of on-trial, non-displaced scoring. This was of interest as such a relationship would suggest that, even though participants could not reliably report whenever they were correct or not, there could yet be some unconscious processing of accuracy information. Another relationship of interest concerned whether on-trial, non-displaced scoring could be reinforced if the targets on neighboring trials were of the same or different alternatives.

More recent research has pursued the relationship of displacement to acute and trait-like psychological factors. Acute factors have appeared to be arousal and emotional intensity; even in his first report, Abbot suggested that the effect was most prominent in the presence of illness and fatigue. Studies led by James Crandall, during 1980-2000, suggested that displacement is reliably associated with the trait of imagery ability. He introduced the term psi-missing displacement effect (PMDE) to denote his consistent observation of matches of responses to targets one removed by trial from the assigned target when there was a below-chance correspondence between responses and the assigned target.

In 1992, Norman Don and associates (University of Illinois, and Kairos Foundation, Chicago) reported that displacement could reliably occur with a periodic difference between target and response trials. They observed this periodic displacement in their own previously collected data; in a randomly selected sample of data independently collected by J. G. Pratt and J. B. Rhine at Duke University in the late 1930s; and in Crandall's data. Similarly to Crandall, they observed that imagery ability had a predictive role in producing the effect.

Understanding the effect

Some researchers have considered displacement to compromise the evidence for psi: Research should be targeted at overcoming its involvement, thereby increasing the accuracy of psi-based detections and identifications in the manner of ordinary sensory perception. Others have considered displacement, however, to be characteristic of the operation of psi. Psychologist Gertrude Schmeidler, of City College, New York, has modelled psi upon normal sensory perception partly on the basis of displacement, particularly with regard to figure/ground relationships. However, Don and associates suggested that the periodic displacement they found in single sets of data indicated a more global and statistical form of perception than is usually appreciated on the basis of sensory perception. The displacement effect, in these ways, has and continues to suggest more concise ways to model psi, and its relationship to sensory perception.

References

1. Alvarado, C. S. (1989). ESP displacement effects: A review of pre-1940 concepts and qualitative observations. Journal of the American Society for Psychical Research, 83, 227-239.
2. Anon. (1938) A scientist tests his own ESP ability. Journal of Parapsychology, 2, 65-70.
3. Carington, W., & Soal, S. G. (1940). Experiments in non-sensory cognition. Nature, 145, 389.
4. Thouless, R. H. (1942). Experiments on paranormal guessing. British Journal of Psychology, 33, 15-27.
5. Abbot, C. G. (1949). Further evidence of displacement in ESP tests. Journal of Parapsychology, 13, 101-106.
6. Bartlett, M. S. (1949). The statistical significance of "dispersed hits" in card-guessing experiments. Proceedings of the Society for Psychical Research, 48, 336-338.
7. Burdick, D. S., & Broughton, R. S. (1987). Conditional displacement analysis. Journal of Parapsychology, 51, 117-123.
8. Greville, T. N. E. (1954). A reappraisal of the mathematical evaluation of the reinforcement effect. Journal of Parapsychology, 18, 178-183.
9. Milton, J. (1988). Critical review of the displacement effect: I. The relationship between displacement and scoring on the intended target. Journal of Parapsychology, 52, 29-55.
10. Russell, W. (1943). Examination of ESP records for displacement effects. Journal of Parapsychology, 7, 104-117.
11. Don, N. S., McDonough, B. E., & Warren, C. A. (1995). Signal processing analysis of forced-choice ESP data: Evidence for psi as a wave of correlation. Journal of Parapsychology, 59, 357-380.
12. Braud, W. (1987). Dealing with displacement. Journal of the American Society for Psychical Research, 81, 209-231
13. Schmeidler, G. R. (1991). Perceptual processing of psi: A model. Journal of the American Society for Psychical Research, 85, 217-236.

See also

Precognition

Retrocognition

• Parapsychology