Other experts questioned the method that Houben was apparently using to communicate. The technique is known as "facilitated communication," in which the patient supposedly directs the hand of a speech therapist who typed out his thoughts.
Houben's doctors said it seemed to be genuine. Until now.
Dr. Steven Laureys, a neurologist at Liege University Hospital in Belgium, one of Houben's doctors, now acknowledges the technique doesn't work and that while Houben is conscious, he is not communicating.
"We did not have all the facts before," he said Friday. "The story of Rom is about the diagnosis of consciousness, not communication."
Houben was injured in a car crash in 1983 when he was 20, and was said to be in a vegetative state, in which a patient is unconscious and there is no evidence of perception or intentional movement.
Based on bedside tests four years ago, Laureys and his team diagnosed Houben as being conscious, and performed brain scans proving his brain activity was more active than other doctors had thought.
Laureys, who was not Houben's treating physician, said the man's family and other doctors brought in a speech therapist to use facilitated communication. "From the start, I did not prescribe this technique," he said. "But it is important not to make judgments. His family and caregivers acted out of love and compassion."
Last November, news of the case first broke in Der Spiegel, a German publication, and The Associated Press and others reported on it as well. Houben's speech therapist claimed she could feel pressure from his hand guiding her on a keyboard. A basic test was performed that ostensibly proved it was Houben who was communicating.
Since then, Laureys has done his own small study of three speech therapists working with minimally conscious patients, including Houben. In two of those cases, including Houben's, the technique failed. Last week, Laureys presented the results at a neuropsychiatry meeting in London.