Nov. 14, 2012 -- Scott Routley hasn't spoken or even followed family members with his eyes since his car accident 12 years ago. But he managed to indicate to doctors this spring that he was not in pain.

And he did it by imagining his playing tennis as researchers watched for certain areas of his brain scan to light up during an fMRI, something he and neuroscientist Adrian Owen worked out as a signal for "no" over a series of sessions. The breakthrough technique proved Routley isn't in a vegetative state, as doctors thought. He's aware of the world around him.

"Some people can look like they're vegetative but still have awareness inside their head. I think it's a very important finding," said Bryan Young, the neurologist at University Hospital in London, Ontario, who has treated Routley for the past decade.

"It really made the point to me that we need to go beyond the clinical evaluation to be conclusive about whether a patient is really in a vegetative state or not."

Young met Routley, 39, after he came out of his coma 10 years ago. The car-crash victim had severe damage to both brain hemispheres, and woke up in what doctors thought to be a vegetative state, which the Mayo Clinic defines as resulting from severe brain damage and renders a person "unaware of his or her surroundings."

Vegetative patients can breathe on their own and usually have basic reflexes, allowing them to make noise, move and open their eyes.

Routley could breathe on his own, but was unable to speak, fixate on people with his eyes, follow people with his eyes or show emotion. He also could not perform simple motions on command, such as wiggle his toes.

Young said Routley's parents and rehabilitation center caregiver often told him they thought he was aware, but he'd always been skeptic. "Enough time had gone by that I didn't think he would improve," Young said.

The standard amount of time to wait for a person to show signs of awareness is six months, he said, "So I was really quite surprised when Dr. Owen found that he had these cognitive responses."

ABC News has been unable to reach Routley's family for comment.

Despite his doubts, Young referred Routley to Owen, a neuroscientist at the University of Western Ontario, to participate in one of Owen's brain-imaging initiatives. Owen has become known for finding consciousness in patients believed to be in vegetative states, and has been published in The New England Journal of Medicine, Nature and other journals.

Owen's technique involves first putting the supposed vegetative patient in a functional magnetic resonance imaging machine, or fMRI, to scan his brain, Young said. He then tells the patient to imagine walking through his home. If the patient can hear and imagine the walk, certain areas of the brain scan light up. Owen then tells the patient to imagine playing tennis, causing different areas of the brain light up.

Owen tells the patient that imagining walking through his home means "yes," and playing tennis means "no," because they make distinctly different parts of the brain scan light up.

In early exercises with Routley, Owen asked him simple questions, such as "Is the sky blue?" and "Is the sky yellow?" Eventually, it becomes clear to Owen that the patient is actually understanding and answering the questions.

In June, when the BBC was filming "The Mind Reader: Unlocking My Voice," Owen was ready to ask Routley whether he was in pain. The scan lit up as Routley imagined playing tennis, meaning "no." He wasn't in pain.

"The stakes are quite high," Owen said. "I wouldn't want to be deciding that Scott isn't in pain if there's a possibility of being wrong."

Because his parents were in the next room, and modern technology allows real-time fMRI readouts, Owen was able to tell the Routleys that their son wasn't in pain right away. Although he's told family members about patient responses in the past, this time was special, Owen said.

"It was the first time I asked a question of a patient that would have some significance for their condition," Owen said. "That science for me was a major landmark moment. They [Routley's family] have known for some years that Scott had some residual abilities. They were relieved that we were able to determine this with the fMRI and provide a little more information with the good news that he's not in any pain."

Owen's colleague John Connolly, a neuroscientist at McMaster University in Ontario, began studying whether supposed vegetative patients were aware in the mid-1990s. He notably used an EEG --electroencephalogram -- to determine that a patient who'd been stabbed in the head and rendered mute could discern whether a sentence made sense. When he said a sensible sentence, the scan showed one kind of brain activity, and when he said a nonsensical one, the scan showed another kind of brain activity.

Connolly said about a dozen labs worldwide have worked at finding awareness and channels of communication with these patients for 20 years, and Owen made an important step forward.

"The whole idea of this interaction with patient, not just passively observing them but trying to engage them, is a very big deal," Connolly said, adding that in many health-care systems, patients are denied certain therapies if they seem uncommunicative because they're a thought to be a lost cause.

"I think the era of judging patients with communication problems, judging on purely behavior, I think those days have to end."

Since June, Owen has met with Routley two more times, focusing on whether he knows who he is or why he is in the hospital -- all as yes-or-no questions -- but Owen can't reveal the answers because he intends to publish the results in a medical journal within the next several months.