The amnesia reported by an Olympia man who turned up in Denver — memory loss so severe that a person cannot remember his or her own identity for a long period of time — is so rare that very little is known about it, experts said yesterday as the man returned home to Washington.

"It's extremely, extremely unusual," said Dr. Murray Raskind, chief of psychiatry at the Veterans Affairs medical center in Seattle.

Jeff Ingram, 40, reported that he had wandered the streets of Denver before he "woke up" and asked doctors and police there for help in learning his own identity.

After reportedly attempting to discover his identity for weeks, he was identified Sunday by his fiancée, Penny Hansen of Olympia, after she saw him on a television news report.

The couple were reunited Monday morning after Ingram flew to Seattle-Tacoma International Airport. But he did not recognize Hansen, their pets or their home, said Marilyn Meehan, a family friend.

"They're taking it one step at a time," said Meehan.

Ingram and Hansen have declined interviews.

Ingram had disappeared after leaving Olympia on Sept. 6 to drive to Alberta, Canada, to visit a friend who is dying of cancer. A missing-person report was filed when he didn't show up in Alberta and had not arrived at the home of his fiancée's mother in Bellingham, where he also had scheduled a visit.

Denver police said that Ingram had been diagnosed with "dissociative fugue," a disorder in which a person unexpectedly begins traveling and then has no idea who he or she is.

The condition is not due to drug abuse, medication or a medical condition such as epilepsy, according to a clinical manual on mental disorders. It is most often related to stressful life events.

Though extended amnesia can occur, recovery is usually rapid, says the Diagnostic and Statistical Manual of Mental Disorders.

Meehan said Hansen believes the stress of the impending death of Ingram's friend triggered his condition.

Ingram's friends have reported that Ingram had a similar episode about 10 years ago, after he was beaten and robbed while on the way to a grocery. He was found nine months later in Seattle after being treated at Harborview Medical Center, friends said.

On Monday, both Raskind and Dr. Elaine Peskind, also a VA psychiatrist, said the condition has not been well studied because it is so rare. Only about 0.2 percent of the population has ever been diagnosed with the disorder.

During extremely stressful events such as war or natural disasters, the prevalence may increase, according to the psychiatric manual.

A person with the condition may travel for hours or days to months, wandering thousands of miles.

The person usually appears normal and doesn't attract attention until he or she is unable to remember recent events or his or her own identity.

Warren King: 206-464-2247 or wking@seattletimes.com