Pop queen Carly Simon, whose hit "You're So Vain" was No. 1 on the charts in 1973, still struggles when she talks about the panic attacks that nearly crippled her successful singing career.
"I think it's the whole experience of being in front of people, exposing yourself and your talent is so unnatural," the still-striking singer said in an interview last week.
Simon was so paralyzed during a 1981 concert in Pittsburgh that audience members swarmed the stage to help her, rubbing the singer's arms and legs. She made it through that show, but during the second one, she collapsed in front of 10,000 fans.
Now, at 62, Simon has just released her first album of original songs in eight years, "This Kind of Love," and has launched a string of appearances that will test her ability to deal with the anxiety disorder that has haunted her for decades.
She began today with a live performance on ABC's "Good Morning America," followed by more performances on TV's "The Rachel Ray Show" and "The Ellen DeGeneres Show," leading up to the real test: a live concert in Miami on May 16.
Simon is not alone. The National Institutes of Health reports that 40 million Americans experience some form of anxiety disorder, causing their lives to be filled with fear and uncertainty. Of those, about 6 million have disabling panic attacks, twice as many of them women.
The singer says she has overcome "to a certain extent" the attacks that began in the early 1960s, using unorthodox techniques to keep her panic at bay.
At the height of her anxiety in 1996, during her very public breakup with singer James Taylor, she agreed to perform at then-President Clinton's 50th birthday party at Radio City Music Hall in New York City.
Before coming on stage, she asked the band's horn section to spank her, a technique she used to calm herself down.
"The whole orchestra was spanking me [on the bottom]," Simon explained. "The curtain went up and the trumpet player was off his perch and spanking me, and I don't think anyone knew it was happening. He stopped just in time."
Panic attacks are unlike the usual jitters that accompany speaking in public or a first date. Sufferers like Simon report a pounding heart, sweating and weakness. Some experience tingling hands, nausea or other smothering sensations. They usually produce a sense of unreality, a fear of impending doom or losing control.
Other high-profile stars have publicly confessed to experiencing panic attacks.
"American Idol's" Clay Aiken said his were triggered by the death of his stepfather and increased as he rose to fame. He later overcame his anxiety with the antidepressant Paxil.
The most famous of the stage-struck stars may be singer Barbra Streisand, who during a 1967 concert in New York's Central Park forgot the words to a song.
She was so traumatized by panic attacks, she was unable to sing publicly for 27 years. She made a comeback tour in 1994 after playing small venues and moving up to bigger venues.
Child actress Drew Barrymore, who overcame drug and alcohol addiction, admitted in 2006 that she was taking medications to deal with panic. Others like cooking show host Paula Deen, actress Kim Basinger and singer Donny Osmond have shared their stories of anxiety.
One of the most surprising victims of panic disorder may be Sigmund Freud, the father of modern psychiatry, who later dedicated his life to researching anxiety.
Another was the Shakespearean actor Laurence Olivier, who was known to regularly vomit before each stage performance.
All share the same "fight or flight" response -- the brain's reaction to perceived danger.
That mechanism normally serves as a protective function, but during a panic disorder, a switch in the brain turns it on when there is no real threat. Attacks are part-biological and part-learned, and they tend to run in families.
"All of a sudden they get a burst of anxiety and they don't know why and where it is coming from," said Jeff Szymanski, director of psychological services at the OCD Institute at McLean Hospital in Boston, one of the nation's leading psychiatric centers. "It's very frightening and feels like something is wrong with their body."
Experts say sufferers shun situations where they have experienced fear -- an elevator, a crowded room or, in the case of these celebrities, performing. It becomes a vicious cycle, their brains then reinforce the avoidance response. When left untreated, these attacks can escalate.
Stage fright is one of the most common forms of anxiety disorder -- though some anxiety is shown to be helpful in performing. "One study showed fear of speaking in public was higher than fear of death," said Szymanski.
He said that "facing your fears" is the most effective way to eliminate panic attacks. So-called exposure therapy slowly reintroduces the patient to the feared scene or object.
In Simon's case -- spanking before performing -- can be helpful, though unconventional, said Szymanski, who has not treated her.
"If you think about anxiety, there is a thought or component that exacerbates it," he said. "Carly Simon said, 'If I can do something that gets me into my immediate sensory experience, that keeps me focus on the right now.'"
Medications can sometimes help a patient "get more put together" so they are willing to undergo treatment, according to Szymanski.
But while exposure therapy followed by talk therapy is highly effective, it has the highest drop-out rates. "Most don't want to do it," he said. "They say, 'Give me a pill that makes it go away,' and try to find a way around it."
Panic attacks tend to occur alongside other mental or physical illnesses, including depression or alcohol or substance abuse, which may mask the underlying condition. Many people learn to fear the fear itself, inducing panic attacks through "auto-intoxication." Others believe they are having a heart attack, losing their mind or on the verge of death. They can occur at any time, even during sleep.
Actress Nicole Kidman explained her panic attacks to Vogue magazine in 2002: "I panic in front of all the cameras. My hands start shaking and I have trouble breathing. Tom [Cruise] would always whisper to me that everything was all right."
Willard Scott, spokesman for Smucker's Jam, described his attacks that began decades ago when he was a weatherman for NBC's "Today Show."
"I was sweating profusely, I couldn't breathe, my mind was befuddled. The people in the studio called a doctor because they thought I was having a heart attack," he said.
Sometimes panic attacks are rooted in childhood trauma, according to Helen Resneck-Sannes, a California psychologist and author of "There Really is Something to Be Afraid Of: A Body-Oriented Psychotherapy for the Treatment of Panic Disorder"
"Usually there was a time, which they can usually think back to and remember, but sometimes don't, when they were humiliated," she said.
As a therapist, she teaches patients to feel the body's response to panic (shoulders up, inhaling without exhaling) and then uses breathing and other relaxation techniques to learn to control them.
"It's a step by step process that starts in the body, to calm it down and let it relax with positive images," Resneck-Sannes said. "I have them really stay in touch with what they are feeling in their body and what happens when they have a panic attack, so they have some control over their physiology."
Indeed, Simon told The New York Times in a 1987 interview that growing up she had a "terrible stutter."
"I was treated like a handicapped child,'' said Simon. ''I remember as a very young girl going on stage and playing Amy in 'Little Women,' but because of my stammer, I couldn't even say my opening line."
Her first major attack on stage was in the early 1960s in a performance with her sister, Lucy, as the Simon Sisters. After recording a solo record, she was persuaded to open for Cat Stevens in Los Angeles in 1971. But her anxiety increased and her performances dwindled.
After her million-selling single "Jesse" in 1981, Simon once again tried a tour of large concert halls, but during two shows in Pittsburgh, panic struck.
''I had two choices,'' Simon said. ''I could either leave the stage and say I was sick or tell the audience the truth. I decided to tell them I was having an anxiety attack, and they were incredibly supportive. They said, 'Go with it. We'll be with you.'"
"When the anxiety comes on, the adrenaline is so strong it topples me," she told the Times. "I never know when it's going to happen, except that the larger the audience, the more I feel I've got to lose. I really never wanted to be a performing artist. I just wanted to be a writer.''
But this week, singing alongside her son, Ben, for family, friends and a handful of critics at Joe's Pub in New York City, Simon seemed unflappable. She belted out old favorites like "Anticipation" and "Coming Around Again," as well as her new Brazilian-inspired material.
Simon confessed to using beta blockers before performing, which psychologists say slows down a pounding heart.
"Some people escape with drinking and doing drugs before they go on, I use Inderal," she said.
Still, Simon seems to have mastered her demons, mostly with a bit of self-talk and rituals like digging her nails into her scalp and "scruffing up" her still-flowing blond hair -- and the spanking.
"I don't think the science thing works as well as doing something," she added. "I liked to be spanked and that sounds really kinky, but it's not. I can do it with a rubber band. Yes, it works. It puts the pain I am feeling psychologically into my body. … It gets me out my head."