Brain stimulation produces creepy shadow feeling

LONDON (Reuters) - Stimulating a certain area of the brain can produce a
creepy feeling that someone is watching you when no one is, scientists
said on Wednesday.

Swiss researchers made the discovery while evaluating a young woman for
surgery to treat epilepsy. They believe their finding could help explain
feelings such as paranoia which afflict patients suffering from
schizophrenia.

When they electrically stimulated the left temporoparietal junction in
her brain, which is linked to self-other distinction and
self-processing, she thought someone was standing behind her.

If they repeated the stimulus while she leaned forward and grabbed her
knees she had an unpleasant sensation that the shadowy figure was
embracing her.

"Our findings may be a step toward understanding the mechanisms behind
psychiatric manifestations such as paranoia, persecution and alien
control," said Olaf Blanke, of the Ecole Polytechnique Federale de
Lausanne, in the journal Nature.

The feeling that someone is lurking nearby has been described by
patients suffering from psychological and neurological problems. The
researchers believe the woman was experiencing a perception of her own
body.

"Although our patient was aware of the similarity between her own
postural and positional features and those of the illusory person, she
did not recognize that that person was an illusion of her own body, like
many deluded schizophrenia patients," Blanke added.