We have read Granqvist, Fredrikson, Unge, Hagenfeldt, Valind, Larhammar and Larsson's article [5] entitled "Sensed presence and mystical experiences are predicted by suggestibility, not by the application of transcranial weak complex magnetic fields". Many people have asked us about possible explanations for the discrepancies between the results of the Swedish research group and the results of Laurentian University's Neuroscience Research Group. We offer a few suggestions. In addition, we have attached all of our e-mails with our Swedish colleagues for public record.

Double blind studies are essential when exploring these phenomena. In all of our major studies [9-12,15] involving hundreds of subjects during the last 20 years the subjects were not aware of their experimental conditions and experimenters were not familiar with the hypotheses being tested or both were not aware of the experimental condition. Subjects were randomly or serially allocated to conditions. The person generating the hypothesis never had direct contact with the subjects.

These precautions are essential because application of specific patterns of weak (1 microT to 5 microT) complex magnetic fields over the right hemisphere enhances suggestibility [6]. We have repeatedly emphasized the importance of the context and the participants' beliefs, expectancies, and temporal lobe "sensitivities" with respect to how they interpret the experiences once they have been elicited by the experimental fields [4,10]. Although we applaud the enthusiasm of Granqvist et al [5] to replicate our research, their methodology deviated significantly from the procedures known to evoke an experimental sensed presence.

The mean and standard deviation for the score for the incidence of sensed presence for the Granqvist et al [5] study for both their experimental (magnetic field) and sham groups (M=0.3, SD=0.5 and M=0.3, SD=0.5) were identical to scores for sham field groups in our studies (M=0.3, SD=0.5). The mean scores for this scale when the appropriate fields are applied are 0.8 or higher. The likelihood that Swedish and Canadian students differ in their temporal lobe sensitivity is not likely because the equivalent scores for the former were .34 (10.3/30) and for the Canadians (n=1,500 over a 20 year period) have been 0.32 (SD=.15). We suggest the subjects in their experimental group never received an effective field configuration.

We are assuming they followed our usual protocol and verified the presence of the field and the appropriate acoustic signature (timing) of the field before each subject. If this was followed, there are three possible explanations for the discrepancy between the results of our multiple studies over 20 years involving dozens of experimenters and the results of Granqvist et al [5]. All of these possibilities assume there are no nuances in local geomagnetic or structurally recondite factors, at present not measured, that are responsible for the discrepancy.

First, the software (Complex 1.15) to generate the magnetic field configurations was designed for XT and 286 IBM PCs using DOS. Specific calibration programs are required when more advanced PCs or WINDOWS is employed. Faster computers and WINDOWS in particular distort the timing of the point durations and disconfigure the temporal patterns of the applied magnetic fields [7]. Reliable, real time values for the point durations are critical in this research [3,16,16]. For example even the "Thomas" pattern, when presented in the reversed temporal sequence, is less effective for producing the sensed presence. In several rat studies [8] the potency of analgesia from these applied fields can be eliminated, similar to changing the impact of a drug by changing the position of an atom, by subtle changes in timing.

Second, Larsson and his colleagues had told us in November 2000 when they visited the lab that they would be employing the equipment to discern the effects of weak magnetic fields for a PET (Positron Emission Tomography) study. Exposure for 15 min to a particularly pattern was suggested for this context, not for a phenomenological or experiential study. Both our rat and human studies indicate that exposures of between 20 and 40 min are required for maximum response to weak magnetic fields [1,2,12,14]. The time required for electroencephalographic changes, such as altered proportions in alpha rhythms or "entrainment" requires more than 15 min of exposure to the fields.

Third, our basic protocol is for the subject to be blind folded and to sit in a comfortable arm chair that is housed within an acoustic chamber (which is also a grounded Faraday cage with the dimensions 2.74 m x 2.54 m x 1.98 m, high). Ear plugs, confined spaces (such as the 1.4 m by 1.4 m box in the Granqvist study) and a requirement to maintain closure of the eyes (no blindfold) interfere with the process. The authors did not indicate the instructions given to the subjects. Our instructions always emphasize that the experiences are subtle and request the subject to just experience whatever happens without labelling the experiences.

We congratulate our colleagues in Sweden for the courage to begin the steps to replicate experiments that may allow neuroscience to systematically explore experiences hereto attributed to mystical or religious sources. However, the importance of replicating the specific timing and pattern of the magnetic field is as critical in this area of science as carefully adhering to the steps of synthesizing a compound is in organic chemistry. We also suggest that more frequent collegial contact is maintained between research groups borrowing the others equipment so that changes and updates can be communicated.

Email Correspondance

References
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