The Replication, and a Disagreement Left Open

In 2005 a Swedish group led by Pehr Granqvist ran a double blind version of the experiment, in which neither the participants nor the experimenters in the room knew whether the field was on. The reported experiences occurred, and they tracked measures of suggestibility and of absorption taken beforehand rather than tracking the field, with participants in the sham condition reporting them as often as those exposed. The authors concluded that suggestion, in a dark and quiet room, with an expectation established in advance, accounted for the results.

Persinger disputed the replication on technical grounds, arguing that the equipment had not been set up correctly, that the field patterns and timings were not those he used, and that the exposure durations differed. The Swedish group answered that they had used his apparatus and his parameters. The exchange did not converge, and the disagreement was never closed before his death in 2018. The atlas records it as an open dispute in the literature rather than as a refuted claim or an established finding, which is the accurate description and also the more useful one, since the design question at issue, how to blind an experiment whose whole subject matter is expectation, applies well beyond this case.