In belonephobia, the most prevalent form of needle phobia, the mere sight of a needle, triggers a physical domino effect known as a vasovagal reaction: a central nerve flares up, then blood vessels dilate, blood pressure drops and the person faints.
For many, it's not just the prospect of getting a shot but sensitivity to the actual pain of the shot that's at the root of their phobia.
To administer an injection, a health care provider must navigate carefully through tissue, tiny veins and nerves to an injection site. Extra movement can push medication into the wrong layer of tissue, causing weird sensations, or push a needle through the other side of the vein, necessitating a repeat try.
"When we do a puncture, we go into a network of small nerves," said Dr. Sudhir Diwan, director of pain medicine at Weill Medical College of Cornell University in New York. "When someone jumps, there can sometimes be a nerve injury, and that causes more pain."
Fortunately, nonfainting needlephobes such as Lamb may not have to wait long for science to find a physical rationale for their fear. Researchers at Emory University in Atlanta are already beginning to use MRI scans to map feelings associated with dread in the brain. Unlocking these secrets may eventually lead to new approaches that will take the sting out of shots for those with a fear of needles.
For those who have never experienced persistent sexual arousal syndrome, or PSAS, its symptoms may seem more like a godsend or a dirty joke than a debilitating condition.
However, for the women who experience PSAS -- which causes them to live perpetually on the brink of orgasm -- the condition is a nightmarish curse. And up until 2001, it was a curse that didn't even have a name.
"I thought I was alone in this," Heather Dearmon, 34, of South Carolina, told ABC News' "Primetime." "And this is after seeing every kind of doctor imaginable -- gynecologist, psychologist, psychiatrist -- you know, everything. And none had ever heard of anything."
Getting relief from the condition is often as elusive as sympathy. The sensations, which are not brought about by fantasies or other sexual thoughts, are often only partially relieved through orgasm. For some women, even sex does not help quell their arousal, and on occasion can even make the sensations worse.
Dr. Irwin Goldstein, a professor of surgery at the University of California at San Diego and the head of the sexual health program at Alvarado Hospital, studies the condition and says understanding of it is spare, even within the medical community.
"Every lecture I give on this, there's always smirks in the audience: 'Oh, I wish my wife was like this.' These are professional physicians," Goldstein said. "And I said, 'No, no, you're, you don't really want this. You do not want your wife to have this, please.'"
Indeed, the mortifying nature of PSAS leads Goldstein to believe that perhaps thousands of women have the condition and don't seek a doctor's help.
"To me, this is a sickness," Dearmon said. "This is not ... something we've chosen. ... I would rather never have another orgasm in my life for the rest of my life than to have this problem."
While it may be true that musical taste resides in the ear of the beholder, it is somewhat less common that a song can send a listener into an epileptic seizure.