How would you like your worst fear physically removed from your brain, never to bother you again? That's exactly what seems to have happened to one man who had an irrational fear of spiders. Interestingly, the phobia was eliminated on accident - a happy consequence of a very serious procedure.

A study of this remarkable medical phenomenon was recently published in the journal Neurocase: The Neural Basis of Cognition, and details how a 44-year-old business man utterly forgot his fear of spiders following the removal of part of his brain.

According to the study, the patient had been suffering from a rare condition called sarcoidosis, which can cause damage to the skin, lungs, and even the brain. Damage to his amygdala - the brain region associated with emotional reaction - in particular was somehow leading to severe and sudden seizures.

To combat this life-threatening condition, doctors felt it prudent to remove the damaged portion of his brain in a painstaking procedure.

Happily, the procedure went well, but soon after the operation the patient noticed two things. He had suddenly developed a remarkably unusual stomach-lurching reaction to music, and his irrational fear of spiders - a phobia he had lived with all his life - was no longer a problem.

According to the study, the reaction to music eventually abated, but his intense fear of spiders, called arachnophobia, never returned.

Nick Medford, of the Brighton and Sussex Medical School, observed the man for some time, running various tests, and eventually helped author the Neurocase study.

He told New Scientist that his observations led him to believe that the removal of part of his amygdala had inadvertently shaved away the part of his brain that sparks "quick and dirty panic responses" - that is, fear that cannot be reasoned with.

Unfortunately for Medford, the man's sole phobia was spiders, and he declined to undergo further testing. However, the researcher says he will have other opportunities to study this stunning phenomenon.

"It's not uncommon for people to have temporal lobe surgery for severe epilepsy," he explained. "And arachnophobia is supposed to be reasonably common. So we might be able to test people for that phobia, or any other kind, before and after surgery."