Out-of-Body Experience: All in the Mind

As a person with an interest in neurology, I often get asked questions about the brain. They are usually not simple questions like, “tell me about the visual pathway” or “why are some people left-handed,” rather; the more popular questions are often spiritual or paranormal in nature. I am often asked:
“What is consciousness?”
“What is the soul?” and
“How do you explain an out-of-body experience?”

The first two are delightful topics for a heated discussion, but to be honest they are probably better suited for a Rabi or Priest than a scientist.
The last one was a real stumper, and I could only theorize about what was going on. Now there is research that may be leading us in the right direction toward unraveling this mystery.


I myself have had an out-of-body experience. I was in the hospital by my friend’s side after he had been in a car accident. He was not hurt too badly, but a combination of late night sleepiness, dehydration, and possibly some chemicals in the air of the ER caused my consciousness to seem to “float” above myself, until I fell backward and hit my head in an embarrassing display of girlish fainting.

Now scientists can replicate the experience, sans late-nigh ER visit. They have discovered the area of the brain that seems to be responsible for the out of body experience, an all time favorite of mine, the angular gyrus.


Lying just caudal to the auditory centers, rostral to the vision centers, and below the kinesthetic sensory cortex, the angular gyrus (both in the left and right hemispheres) is a sort of integration ground for sensation. It is no surprise that stimulation of this tissue creates a disjunction between the senses, causing patients to have an odd sensation of body “shadowing” or a full out-of-body experience.

In Geneva, a wealth of knowledge has come from two epilepsy patients who have had dozens of electrodes implanted in their brains to pin-point the cause of their epilepsy. The women both experienced out-of-body sensations when their angular gyrus was stimulated.

The neurologist, Dr. Olaf Blanke, reported that his patients had normal psychiatric history and good mental health before the experiment.
One patient reported feeling as though she were at the ceiling and gazing down on her legs when a current flowed through the electrode near her angular gyrus. The sensation subsided when the current was off. The other woman reported a shadowy presence that seemed to loom beneath her and mimic her every move. When he turned the current off, the sensations again subsided.

Dr. Blanke’s published discoveries regarding the angular gyrus can be found here: http://www.nature.com/nature/journal/v443/n7109/abs/443287a.html, and here: http://intl-brain.oxfordjournals.org/cgi/content/abstract/127/2/243

Source:
From the article “One Body When the Brain Says Two”
Forwarded to me via Karen Cassil
Related articles: http://www.nature.com/nature/journal/v443/n7109/abs/443287a.html http://intl-brain.oxfordjournals.org/cgi/content/abstract/127/2/243
Image sources:
http://www.snibbe.com/scott/body_image/shadow_bag/index.html
http://www.answers.com/topic/angular-gyrus