Following a Bright Light to a Calmer Tomorrow

Researching Near-Death Experiences

From 9 to 18 percent of people who have almost died, Dr. Greyson said, later report having had near-death experiences. As medical techniques to save patients become increasingly sophisticated, that number is likely to grow.

In the early 1980's, a nationwide Gallup poll found that eight million Americans said they had had near-death experiences. By the late 90's, 15 million people reported having had them.

Almost everyone, at some point in life, experiences a moment of fear and anxiety after a catastrophe. For some people like those with post-traumatic stress disorder, the effects can linger for years, returning as flashbacks, nightmares or emotional numbness.

But people who report having had out-of-body experiences like Ms. Huesgen, who suffered a near-fatal reaction to an influenza shot 34 years ago, exhibit the reverse. Their lives are changed.

They switch careers and adopt new values. Many fears they had are erased.

Most doctors dismiss such events as hallucinations caused by medication. Other experts suggest that the illusions are caused by oxygen deprivation or the last-minute firing of neurons in the visual cortex.

Dr. Greyson theorizes that the experience may be a protective mechanism that insulates some people against developing post-traumatic stress disorder. Certain personality traits, he suggests, may make some people more likely to have near-death experiences, while others are predisposed to developing severe psychiatric illnesses.

The evidence of active coping and physiological differences in people who have had near-death experiences squares nicely with that theory, Dr. Greyson said.

But there is still a question of cause and effect.

"We don't know yet whether these were pre-existing characteristics that caused the N.D.E. or whether they are the result of the experience," he said.

The answer may soon be clear. In a study that began this year, Dr. Greyson is interviewing a large group of heart patients before they undergo surgery to implant automatic defibrillators in their chests.

In the operation, the patients are briefly put into cardiac arrest, setting the stage for some to have near-death experiences. Several months later, Dr. Greyson will interview them again, looking for any near-death aftereffects.

"There are so many things to measure — anxiety, depression, adjustment, acceptance of death," he said. "We're still just scratching the surface. There's a whole lot more to be done."