NEW YORK — Every day millions of Americans live in dread fear of fear itself.

In their lifetimes, 26 million will be visited by irrational terror, some by a choking, heart-racing, dizzying, paralyzing panic so severe that they think they are dying or going crazy.

For some, it means insulating themselves, locking themselves up in their homes alone, or, paradoxically, making sure that they are always with someone they trust in circumstances they can trust.

Each new attack reinforces the last.

Dr. Jack Gorman and his colleagues at Columbia University's Department of Psychiatry and the New York State Psychiatric Institute say patients with panic disorder often describe their first panic attack with remarkable vividness. They recall in detail what they were doing on the day of the first attack, what happened, and how they felt afterward.

"Such descriptions convince the clinician that panic attacks are devastating," Gorman says. "Feelings of dread, fear, and a sense of impending doom overwhelm the patient who becomes lightheaded, dizzy and faint."

Dr. Alan Goldstein of Philadelphia's Temple University, says, "At the core of all this is a learned fear of fear.

"Just as someone bitten by a dog comes to fear dogs, so does one bitten by panic come to fear panic. Just as the body mobilizes for an anticipated dog attack with the 'fight or flight' response, so it does with anticipated attack from within by panic."

An estimated 9% of Americans are afflicted with anxiety-phobic disorders in any six-month period, a third more than those suffering from alcohol and drug abuse, and almost a third more than those suffering from depression and related disorders.

Doctors who intervene to break the chain of fear frequently force the patient to face his fear. Dr. David Clark of England's Oxford University says patients sometimes interpret an increased heart rate as evidence of a heart attack, or breathlessness as a sign they are about to suffocate, or racing thoughts as a sign they are going mad.

He asked one patient who feared that he was going mad if he had ever actually gone mad. The patient said no. Then why not, asked Clark, and the patient said he always mastered his thoughts just in time. Then, if you can do that, said Clark, then certainly you could reverse this skill and make yourself go mad, at which point the patient realized that he couldn't go mad, even if he wanted to.