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Christopher French’s “Haunted Room” Experiment: A brief commentary.
Todd Murphy, 2014.
I would like to take a moment to write about Christopher French’s “Haunted Room” experiment. I consider it to be flawed. I have no expertise in the role of ultrasound in anomalous experiences, so I won’t comment on that aspect of his paper, but I do have experience with rendering Persinger’s signals so that they can be accurately produced with computer sound cards.
Christopher French set up an experiment in which he created a room and filled it with magnetic signals (fed by an audio source) and ultrasound. He wanted to see if subjects and controls had the same response to these stimuli, which have been implicated in paranormal experiences, including ghosts and poltergeist. French did not succeed in creating a synthetic “haunted room”. His paper has been touted as a refutation of Persinger’s work with magnetic stimulation, but French assumed that getting his stimuli right would be easy. Its not. Rendering the signals correctly is a specialized job in an area where French (et al.) had no experience.
Here is one quote from French (at al.’s) paper:
“The Persinger burst pattern was generated by constructing a table of values from the graph of the waveform used and then converting these numeric values into a 16-bit.wav file using Goldwave (software) at a sample rate of 1000 Hz for playback via the computer’s soundcard.”
The Shakti and Shiva signals use a much higher sample rate, and French used a method of rendering the signals I used in their first draft, which Persinger and Koren did not accept (the third draft was the first they accepted). The signals in use at present represent the eighteenth (18th) draft. I will not burden the reader with the history of the development of these signals. I will only say that French made assumptions about rendering Persinger’s signals that aren’t supported in my experience. Going from a graph to an audio signal isn’t enough. His signals never had any chance of success. Rendering the signals isn’t a job for the inexperienced. Simple audio editors aren’t enough. In fact, doing it requires several proprietary softwares. French didn’t mention which type of sound card his computer used, and many of them just don’t have the low frequency response these signals require.
I can say that unless the signals are rendered in ways that overcome specific limitations of all contemporary sound cards, they won’t be Persinger’s signals at all. Anyone who claims that they rendered them using normal sound softwares will be making a false claim. The will not have created the signals.
Further, Persinger’s signals were developed for use in neural stimulation, while French used whole-body stimulation. When Persinger tried the same thing (filling a room with his signals), using his correctly configured patterns, the result was the same as French’s – no result. Whole body stimulation means that the whole brain will be evenly stimulated, while Persinger stimulates only the temporal lobes (in most, but not all, cases), and Persinger makes use of the brain’s hemispheric specializations by stimulating either one or both temporal lobe, a session design feature that can’t happen with whole-body stimulation.
In addition, French also wrote that:
“… all participants were informed in advance that they might experience unusual sensations whilst in the chamber”
This is a radical departure from Persinger’s suggestion that the subjects are participating in a “relaxation experiment”. This suggestion predisposes subjects to relax, but without ‘priming’ them to expect any kind of anomalous experiences.
French (et al.) also wrote:
“It may simply be that our choice of waveform was not suitable for our experimental set-up. We readily acknowledge that ours was a very conservative test of the hypothesis that complex EMFs may induce anomalous experiences in susceptible individuals and feel that further tests of the hypothesis are justified.”
It seems that French (et al.) were not as confident of their results as many of those who have commented on it. He may also have recognized that he used only one of the two signals Persinger uses. Of course, this is speculation. His statement goes beyond the usual “more research is called-for” disclaimer found in so many research papers.
In brief, French’s study started out to answer a reasonable research question, but he seems to have made assumptions without consulting experienced colleagues. One of these is that the information content in the geomagnetic field that Persinger says contributes to UFO reports, poltergeists, and ghostly sightings is the same as the information in the signal French tried to use (and they are not, and Persinger doesn’t claim they are). Second, that the easiest-to-render audio signal will be effective (it’s not).
If French had consulted with Persinger or I before he began this experiment, he would have been told all of this. However, he is critical, perhaps even hostile, towards belief in paranormal phenomena. The common and unfortunate practice (among both skeptics and believers) is to avoid contact with scientists who disagree with them when setting up their experiments. The Shiva and Shakti neural stimulation software’s end-user license agreements specify that agreement about research methods using them must come before experiments for publication (ensuring input from experienced lab techs), and hopefully this will ensure communication between colleagues before such experiments begin in the future.
Communication between colleagues is one of the foundations of science, especially when they are not in agreement.
French CC, et al., The “Haunt” project: An attempt to build a “haunted” room by manipulating complex electromagnetic fields and infrasound, Cortex (2008), j.cortex.2007.10.011.
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