Brain Stimulation Produces "Out-of-Body" Experience
By Susan Jeffrey
Medscape Medical News
November 6, 2007 — Researchers are reporting they were able to repeatedly and reliably elicit an "out-of-body" experience in a patient in whom electrodes had been implanted to suppress tinnitus.
"We were able to reproduce the effect at will and in a completely placebo-controlled way, because the patient was not able to tell when the stimulator was on," first author Dirk De Ridder MD, PhD, from the department of neurosurgery at the University Hospital Antwerp, in Belgium, told Medscape Neurology & Neurosurgery.
Their report appears in the November 1 issue of the New England Journal of Medicine.
An out-of-body experience is a brief subjective episode in which the self is perceived as being outside of the body, with or without the impression of seeing the body from an elevated and distanced perspective, the authors write.
The case reported here was of a 63-year-old man from Denmark who had been referred to their institution and received implanted electrodes overlying the temporoparietal junction on the right side in an attempt to suppress intractable tinnitus.
They had been using a new and more powerful method of stimulation and found the patient had an out-of-body experience with this method. "We stopped immediately and noted the exact parameters of the stimulation," Dr. De Ridder said.
With the patient’s permission, they were able to exactly reproduce the sensation, but only at these certain parameters. "When we lowered the stimulation by just 1 V, it didn’t happen," he noted.
Because the experiences lasted around 17 seconds, they were able to perform positron emission tomography (PET) scanning in a placebo-controlled way and locate the activation to the temporoparietal junction, or more specifically, the angular–supramarginal gyrus junction and the superior temporal gyrus–sulcus on the right side. Activation was also seen at the right precuneus and posterior thalamus with stimulation, extending into the superior vermis.
"We suggest that activation of these regions is the neural correlate of the disembodiment that is part of the out-of-body experience," they write.
These findings have no implications for the out-of-body experience as it relates to near-death experiences, Dr. De Ridder said. Spontaneous out-of-body experiences have also been previously reported in epileptic patients, those with migraine, and, in a recent report, have been induced in healthy volunteers using a virtual-reality system, although not in this kind of reliable way.
"This is simply a description of the neural network that’s involved in the out-of-body experience," he said.
They have some other patients who have electrodes implanted in the same location and may approach them about participating in a further study of this effect, he said. The institutional review board approval for the first patient was to look at side effects and complications of auditory cortex stimulation, so this study was technically covered by that approval, Dr. De Ridder noted. To study this effect in other patients will require a new application.
The authors report no conflict of interest relevant to this article.
N Engl J Med. 2007;357;1829-1833. Abstract
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