Getting on an airplane, lying still in an MRI machine or even public speaking can paralyze Helen Resneck-Sannes' patients, whose arousal systems are in full-fear mode.
"They take beta blockers or valium and it really doesn't stop the fear," the Santa Cruz, Calif., psychologist said. "The next time they are on the airplane or speaking or claustrophobic, they are still afraid."
Drugs to treat those who suffer from phobias and anxiety disorders have been used for decades with some success, but there is still no medical silver bullet for those who are irrationally afraid or traumatized.
Just this week, scientists at the University of Hiroshima in Japan found a way to switch off the fear center in the brain by injecting a shot of lidocaine, an anesthetic, to the brain -- of goldfish, that is.
The brains of goldfish share many similarities with those of mammals, including humans, according to researchers, who hope to understand more about biological and chemical processes that cause humans to be afraid.
"I think it would be great if someone needs to get an MRI if you could give them a shot of lidocaine," said Resneck, who wrote the 2002 book, "There Really Is Something to Be Afraid Of: Treatment of Panic Disorder."
"On the other hand, if you can find out the reasons for the claustrophobia, it would be better," she said. "But in an emergency, that would be a really good idea."
Fear is the most primal of all emotions, the lynchpin of the "fight or flight" response that protects human beings against danger. But in about 40 million Americans, that mechanism is out of control.
Anxiety disorders are the most common mental illness in the United States, affecting about 18 percent of the population, according to the Anxiety Disorders Association of America (ADAA).
Only about one third of those who are suffering receive treatment, which is usually a combination of drugs and behavioral therapies. They are three to five times more likely to go to the doctor and six times more likely to be hospitalized for psychiatric disorders than those who do not suffer from anxiety disorders, according to the ADAA.
Anxiety disorders develop from a complex set of risk factors, including genetics, brain chemistry, personality and life events.
In the Japanese experiment, researchers taught goldfish to become afraid of a flashing light. Each time the light was switched on, the fish received a low-voltage electric shock.
The fish learned to associate the light with the pain and soon, they became afraid of the light, even without the shock. Scientists noticed that their heartbeats sped up, similar to how humans react when they are afraid.
But when scientists injected lidocaine into the cerebellum part of the brain an hour before the experiment began, the fish showed no symptoms of fear when the light was shone.
Lidocaine is similar to Novocain, which is used by dentists to numb teeth.
Once the lidocaine wore off, however, the fish experienced fear again.
"Chronic anxiety is a huge problem and some of it is perfectly justified, if we are worried about safety or finances," said Bruce McEwen, a neuroscientist at Rockefeller University in New York City.
"The purpose of fear is to alert us to danger and to create memories that allow us to remember," he said. "But abnormal fear and anxiety, we don't like or want that."