A study published last year in a scientific journal claimed to have found strong evidence for the existence of psychic powers such as ESP. The paper, written by Cornell professor Daryl J. Bem, was published in The Journal of Personality and Social Psychology and quickly made headlines around the world for its implication: that psychic powers had been scientifically proven.
Bem’s experiments suggested that college students could accurately predict random events, like whether a computer will flash a photograph on the left or right side of its screen. Scientists and skeptics soon raised questions about Bem’s study and methodology. For example Ray Hyman, a professor of psychology at the University of Oregon at Eugene who previously evaluated the efficacy of psychic abilities for the Pentagon, found many flaws in Bem’s study. At the time Hyman told Discovery News, “I’m puzzled as to how four referees and two editors of a prestigious journal could allow Bem to publish as 'experiments' studies that violated accepted methodological standards.”
As I wrote when I first reported on this study, “Bem has replied to his critics and stands by his findings. Ultimately, of course, either the findings will stand the test of time and be replicated by other researchers, or they won’t.”
Replication is of course the hallmark of valid scientific research—if the findings are true and accurate, they should be able to be replicated by others. Otherwise the results may simply be due to normal and expected statistical variations and errors. If other experimenters cannot get the same result using the same techniques, it’s usually a sign that the original study was flawed in one or more ways.
So far it’s not looking good for psychics; the experiment was replicated, and failed. A team of researchers Professor Chris French (Goldsmiths, University of London), Stuart Ritchie (University of Edinburgh) and Professor Richard Wiseman (University of Hertfordshire) collaborated to accurately replicate Bem’s final experiment, and found no evidence for precognition. Their results were published in the journal PLoS ONE.
Ironically, the publication that had originally published Bem’s study refused to publish the latest research calling that same study into question. “Our submission was rejected without being sent for peer review on the basis that the journal has a policy of not publishing replications,” said French. “Our paper has opened up the debate on the proper place of replication in the scientific literature.”
In other words, The Journal of Personality and Social Psychology’s editorial policies actually violate standards of good science by preventing the publication of studies designed to ensure that research it originally published is valid. As French wrote in a piece published in The Guardian, “Although we are always being told that ‘replication is the cornerstone of science’, the truth is that the top journals are simply not interested in straight replications – especially failed replications. They only want to report findings that are new and positive.” Wiseman said that he hoped that “academic journals and popular media alike will offer the same weight to negative results as given to eye-catching positive results.”
Bem, who had encouraged other researchers to replicate his study, acknowledged that the latest findings do not support his claims, writing that “I believe that Ritchie, Wiseman, and French have made a competent, good-faith effort to replicate the results of one of my experiments on precognition…. Nevertheless I consider it premature to conclude anything about the replicability of my experiments on the basis of this article…. In mainstream psychology it usually takes several years before enough attempted replications of a reported effect have accumulated to permit an overall analysis.”
As before, Bem has replied to his critics and stands by his findings. Ultimately, of course, either the findings will stand the test of time and be replicated by other researchers, or they won’t.
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