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Hypnotism. Photo by AP
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Shiran Granot
Hadassah hospital in Jerusalem. Photo by Shiran Granot

Researchers at the new center for the treatment and study of hypnosis at Hadassah University Hospital, Ein Karem, are trying to shed light on the influence of hypnotic states on the human mind.

In one study, a technique called magnetoencephalography magnetic enchephalography (MEG ) system - which maps brain activity by recording magnetic fields produced by electrical currents in that organ - has been used for the first time to "read the mind" during hypnosis.

The project, headed by Drs. Eitan Abramowitz and Avi Goldstein, examines neurological activity during what is known as "out of body experiences."

"The subjects are students who have already demonstrated a high ability to be hypnotized, and easily enter deep trances. Their brain activity is compared to other regular, control subjects," explains Abramowitz, noting that each subject is hypnotized for 30 minutes.

A comparison of data has already pointed to the part of the brain which is probably influenced by hypnosis - the area where the temporal lobe connects to the parietal lobe in the cerebral cortex. Abramowitz notes that this is a "sensitive area which is subject to exceptional electric activity among epileptics who develop pathological experiences and feel that they leave their body."

The researchers are also examining experiences of simulated paralysis in certain limbs that are introduced during hypnotic trances. Such temporary phenomena, which have no organic explanation, have in the past been explained in medical literature as stemming from "hysteria."

"Paralysis occurs when the brain is inattentive to a certain part of the body, or intentionally neglects and neutralizes a certain area," Abramowitz says. "Such knowledge can promote the understanding of how hypnosis works, and establish its position in science and medicine as determined by scientific instruments of research."

In a recent study of brain activity during hypnosis using an MRI scan, German researchers from the University of Hamburg witnessed increased activity in the precuneus of the parietal lobe in the cerebral cortex.

MEG, which is done in Israel only at Bar-Ilan University, involves noninvasive mapping of brain activity, without any radiation, via sensors which measure magnetic fields in the brain's nervous system at intervals shorter than a thousandth of a second.

Meir Wolf, a PH.D student at the MEG and EEG laboratories at Bar-Ilan explains that, "as opposed to using devices that measure electrical activity, [examination of] magnetic fields have an advantage since they aren't distorted by the skull's form or other biological substances."

The MEG mapping device is also used for diagnostic purposes such as detecting epileptic centers in the brain, before surgery.

Another study currently under way in the Hadassah hypnosis center, in cooperation with Dr. Netta Levin, director of the neurology laboratory, is focusing on how the brain's physiological mechanisms are affected by changes of memory brought on by hypnosis. The research, carried out using an MRI scanner, examines healthy subjects, most of whom are doctors and students, who are first asked to conjure up a frightening image of a person connected to a negative memory.

"Everyone has a past negative experience connected with someone who harmed him or degraded him, and we concentrate on the face in order to focus the examination on the brain area affected by visual memory," Abramowitz explains. In the next stage, the subjects are scanned by an MRI, and then are hypnotized for several minutes, during which the researcher "deletes" the memory of the threatening face. Afterward another scan is performed to examine whether any change in brain activity has occurred as a result of the hypnosis.

The researchers are focusing here on the occipital lobe, which is connected to visual memory. Initial findings point to increased blood flow in this area when the subject tries to recall the image that was recently "deleted."

Both studies have been approved by the Health Ministry's national advisory committee, which overseas implementation of the 1984 Hypnosis Law.