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Saturday, May 05, 2012

Neurophysiological Explanation for the Perception of Poltergeists



Poltergeists are defined as paranormal, mischievous ghostly presences that appear to a select group of people. As paranormal entities, they are beyond investigation by rational scientific means. Or are they? Odd sensations, visions, felt presences, out-of-body experiences, etc. have all been explained by unusual brain activity. Hence, neuroscientists should consider that poltergeists exist in the mind of the perceiver, not as a physical reality in the external world.

A new paper by parapsychologist William G. Roll and colleagues reported on the case of a woman who experienced paranormal phenomenon after suffering a head injury (Roll et al., 2012):
People who report objects moving in their presence, unusual sounds, glows around other people, and multiple sensed presences but do not meet the criteria for psychiatric disorders have been shown to exhibit electrical anomalies over the right temporal lobes. This article reports the striking quantitative electroencephalography, sLORETA results, and experimental elicitation of similar subjective experiences in a middle-aged woman who has been distressed by these classic phenomena that began after a head injury. She exhibited a chronic electrical anomaly over the right temporoinsular region. The rotation of a small pinwheel near her while she 'concentrated' upon it was associated with increased coherence between the left and right temporal lobes and concurrent activation of the left prefrontal region. The occurrence of the unusual phenomena and marked 'sadness' was associated with increased geomagnetic activity; she reported a similar mood when these variations were simulated experimentally. Our quantitative measurements suggest people displaying these experiences and possible anomalous energies can be viewed clinically and potentially treated.
Previous work by Roll and Michael ["god helmet"] Persinger (2001) suggested that individuals who experience "anomalous energies" around them might have complex partial epilepsy with a temporal lobe focus, usually on the right side.

The current patient, Ms. S, was in a motor vehicle accident which resulted in two days of coma and a severe brain injury. After the head injury,
...the relationship with her first husband deteriorated because he insisted she was not the same person. This ‘change in personality’ is a frequent report by spouses of individuals who have sustained TBIs. According to her reports one night he tried to kill her. The anomalous phenomena began that night and have been intermittent since that time. Their intensity and frequency have increased during the last 2–3 years. The anomalous phenomena include mechanical, electronic, and visual effects. She reports experiences of sounds, perceived as ‘taps’ that she estimates to be between 3 and 4 Hz with sound pressure equivalents between 40 and 60 db. Occasionally there may be a single louder sound. The durations of clusters are often between 3 and 10 seconds with intervening periods of 4–8 or 16–24 seconds. The clusters are usually localized along her left side.

. . .

Ms. S. reported she feels overwhelmed by a deep sadness after the occurrence of the phenomena and cries, even if nothing ‘bad happens’. Since the beginning of these phenomena she hears voices of multiple ‘imaginary’ friends who she has named; the two major ones are identified as male. They presumably help her minimize the distress of the experiences...

EEG recordings revealed chronically abnormal activity at a right temporal lobe electrode (T4), which showed persistently elevated amplitude. Strangely, this enhanced activity declined when the doors to the recording chamber were closed, as in Fig 1C below.

Figure 1. Sample EEG activity over 19 channels displayed by Ms. S. Note the persistent high amplitude (100 μV) over the right temporal lobe compared to all other lobes (about 20 μV). (A and B) are separated by one day. (C) Shows the attenuation of the T4 anomaly after the doors of an acoustic chamber were closed.


The authors attributed this to a reduction of geomagnetic fields, to which the TBI patient is exquisitely sensitive [supposedly]:
The right temporal lobe anomaly attenuated within about 20 seconds to 1 minute after the doors to the acoustic chamber were closed. In addition to providing above average silence, this procedure reduces the static background geomagnetic field from 50,000 nT to about half that value. When the T4 anomaly was not distinguishable and she was sitting within the closed-door chamber she reported experiences as if she was ‘missing’ something that was similar to a ‘craving’.
But maybe she was just more relaxed in the dim lighting and quiet environment of the chamber...

From here on in, the authors resort to bizarre atmospheric explanations: instabilities in global geomagnetic activity and a K-6 level geomagnetic storm accounted for perceptions of tapping sounds in her hotel bedroom window, the presence of ‘entities’, and unusual lights around objects.

Here's my suggestion: Why don't you take a closer look at her EEG activity in relation to these anomalous perceptions, independent of the spooky magnetic fields?? Is it because your research in parapsychology and neurotheology might float away into the ether?


Footnote

1 The young actress here, Heather O'Rourke, died at the age of 12 due to "medical error."


References

Roll, W. G. and Persinger, M. A. 2001. “Poltergeists and haunts”. In Hauntings and poltergeists: Multidisciplinary perspectives, Edited by: Houran, J. and Lange, R. 123–163. Jefferson, NC: McFarland & Company.

Roll, W., Saroka, K., Mulligan, B., Hunter, M., Dotta, B., Gang, N., Scott, M., St-Pierre, L., & Persinger, M. (2012). Case report: A prototypical experience of ‘poltergeist’ activity, conspicuous quantitative electroencephalographic patterns, and sLORETA profiles – suggestions for intervention. Neurocase, 1-10 DOI: 10.1080/13554794.2011.633532


6 comments:

  1. Hmmmm. I'm no EEG expert but I have some experience collecting EEG data and that "high frequency" T4 track looks a bit like a muscle artefact to me.

    Sometimes you get this, almost always over a single temporal electrode. Some kind of muscle twitching away causes a series of sharp spikes.

    I'm not saying that's what's going on there but if this were my data I would be worried...

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  2. Good point! I sort of considered that possibility, which would fit with the "more relaxed in the dim lighting and quiet environment of the chamber" interpretation. If it were EMG artifact, you might also see it at T3, the analogous temporal electrode on the left side. Taking a closer look, however, revealed some additional problems, including the electrode labels: 20 labels but only 19 EEG traces. F8 and T6 occur twice but T5 is missing. This does make me question their data.

    Looking at the paper again to check the purported frequency range for the T4 activity... and it's 20–25 Hz, which might be a little low for EMG?

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  3. I immediately had the same thought as Neuroskeptic: it looks a lot like muscle noise to me.

    Muscle noise has a really broad spectrum but often shows a peak at ~20Hz: http://www.ncbi.nlm.nih.gov/pubmed/12948787

    For a comparison, take a look at Figure 2 in this article on using ICA to remove articles, which shows a remarkably similar pattern
    http://sccn.ucsd.edu/~scott/pdf/PSY00.pdf

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  4. I agree there could be contamination with EMG artifact. In terms of getting a rough estimate of the raw frequency range at T4, it doesn't help that the figure has no time scale. Clarification from examining other sites isn't helped by the confusing labels either (e.g. you really might expect some EMG not only at T4 but also at T3, as in the PDF you sent).

    Given all the geomagnetic crap they talk about in the paper, it's hard to know whether to trust their LORETA analysis, which found the greatest increase in power in the 30 Hz range. There's also the matter of attenuation when the door was closed.

    All that said, there might be some unusual EEG activity along with EMG, although without ICA you really can't say. The reason I consider this is that the patient experienced something different, according to self-report:

    When the T4 anomaly was not distinguishable and she was sitting within the closed-door chamber she reported experiences as if she was ‘missing’ something that was similar to a ‘craving’.

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  5. is this really true? I really want to believe this thing is happening but I believe in that "to see is to believe" saying. but a proof is acceptable. could someone explain to me the causes of this Poltergeists? just because curiosity.

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  6. The influence of Persinger's "god helmet" on brain activity has not been replicated in several well-controlled tests (http://en.wikipedia.org/wiki/God_helmet#Failed_replication_and_subsequent_debate). Also, there are typically many eye witnesses to the poltergeist phenomena that Roll, et al, describe, while sometimes these go unnoticed even by the "focal person" around whom such activity is centered (e.g., Annemarie Schaberl, also an epileptic); it's unlikely that all such people experience the same phenomena in a similar manner while one (i.e., the person associated the poltergeist) does not.

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