When Beki Propst talks about the first 47 years of her life, it's as if she is describing the story of a stranger.
Her former status as an officer for the Colorado Association of Realtors. The printing company she owned. The hobbies she enjoyed. Her black belt in karate.
These are details of a life that her family and others have related to her. But Propst knows that photo albums and anecdotes can sketch only so much of the life she had before the fall of 1997 -- before a massive, grand mal seizure ripped away her connections with her past, stripping her memories bare.
"Now, I'm starting to kind of wonder what kind of person I was," said the 57-year-old from Sterling, Colo. "But it's not really relevant because I don't know that person."
"Everyone I knew before says my personality is the same. But I don't know if I'm the same person."
Details of the rare case continue to baffle doctors. What they do know is that a seizure -- what many neurological experts describe as a severe electrical storm within the brain -- caused Propst's declarative memory to be wiped clean. Facts, events, dates, acquaintances and even her identity were wiped away with it. As Propst describes it, "If I was a computer, it would be like my hard drive was erased."
What remained was her implicit memory -- qualities such as intelligence and work ethic -- as well as her vocabulary and her familiarity with a few dozen songs.
From this, she has rebuilt her life. Her persistence in rejoining the work force has led to stable employment as a custodian at a state facility. She enjoys strong relationships with her family. And she has written a book, titled "Absent Memories: Moving Forward When You Can't Look Back," which documents her experiences.
"Every single person I met said, 'You need to write a book about this,'" Propst said. "I thought, 'What the heck, what do I have to lose?'"
David Ewing of Centennial Neurology in Greeley, Colo., Propst's doctor, said that it is remarkable that Propst has adjusted so well to her new life, which, in a way, began slightly more than 10 years ago. The seizure, he says, effectively disconnected the area of her brain in which her memories were stored.
"The area is still there, still intact," he said. "But it was like someone threw a breaker switch. ... She had a single general event, after which she woke up and all of her memories were wiped out."
Even Propst said trying to appreciate the magnitude of losing one's memories is a mind-bending task. And having been through it, she said many people with whom she talks have little idea of the true impact of the event.
"Some people say to me, 'That must be really wonderful, it would be like being a kid again.' I think it would be wonderful if you could choose which memories to forget. But I don't remember my mother. I don't remember being part of a family. I don't remember being a kid."
Although cases like Propst's are rare, researchers have linked seizures with memory loss for some time.
"[Seizure-related] memory loss is a major concern for patients and has been well recognized since the mid-1850s," said Dr. Orrin Devinsky, director of the epilepsy program at New York University. "Recurrent seizures injure the brain, and the memory centers are particularly vulnerable."