For 23 years, doctors believed a man in Belgium was in a vegetative state, barely able to move or think after a car crash.
Then, doctors studying patients who appeared to be completely unresponsive made a stunning discovery: Rom Houben was in fact awake.
Dr. Steven Laureys of the University of Liege's Coma Science Group, decided to take another look at Houben's brain using the latest imaging technology.
"We put him in the PET scanner, the MRFI," Dr. Laureys told CBS News correspondent Elizabeth Palmer, "and then we saw his brain was functioning normally, so he was not vegetative."
For more than two decades, Houben had apparently heard and understood everything going on around him.
Now, the challenge was to let him communicate.
A caretaker was trained to interpret the tiny movements Houben makes at the keyboard to spell out sentences.
In an interview with the German magazine Der Speigel and reported on by the U.K.'s Daily Mail, Houben wrote that "I screamed, but there was nothing to hear."
For Houben, now 46, it was a liberation.
"I shall never forget the day when they discovered what was really wrong with me - it was my second birth," he wrote.
"All that time I just literally dreamed of a better life. Frustration is too small a word to describe what I felt. . . . I want to read, talk with my friends via the computer, and enjoy my life now that people know I am not dead."
A leading bioethicist, however, expressed skepticism that the man was truly communicating on his own.
Arthur Caplan, a bioethics professor at the University of Pennsylvania, told the Associated Press he is skeptical of Houben's ability to communicate after seeing video of his hand being moved along the keyboard.
"That's called 'facilitated communication,"' Caplan said. "That is ouija board stuff. It's been discredited time and time again. When people look at it, it's usually the person doing the pointing who's doing the messages, not the person they claim they are helping."
Caplan also said the statements Houben allegedly made with the computer seem unnatural for someone with such a profound injury and an inability to communicate for decades.
Asked how he felt when his consciousness was discovered, Houben responded through the aide that: "I especially felt relief. Finally be able to show that I was indeed there."
Rom's mother Fima, proud to show photos of him before the accident, never stopped believing he was conscious.
"He couldn't communicate, but I knew," she said. "I could tell when he was in a bad mood, or when he was in pain."
It was a mother's diagnosis that turned out to be right, even though this patient had to wait more than two decades for medical science to agree.
Dr. Laurey's discovery took place three years ago but recently came to light on the publication of a study on the misdiagnosis of people with consciousness disorders.
(Left: A patient is examined during a scan at the University Hospital in Liege, Belgium, Nov. 24, 2009.)
CBS News medical correspondent Dr. Jennifer Ashton said there are a few reasons why patients believed to be in a persistent vegetative state are misdiagnosed:
"The actual testing could be flawed, or the interpretation of that testing could be flawed. The other thing is they can start to begin a recovery - this usually follows a traumatic brain injury and there can be recovery that happens - it could happen months or years later," she said on CBS' "The Early Show."
For more info:
"Diagnostic Accuracy of the Vegetative and Minimally Conscious State" - BMC Neurology (07.09)