Bradley Crehan doesn’t remember being hit by a car. He doesn’t remember his skull smashing against the road, nor does he remember the first six weeks he spent in a California hospital.

“It’s like I’d gone to sleep the day before it happened,” the 25-year-old told CTVNews.ca. “And then I woke up.”

Were it not for a group of pioneering scientists at the University of California, Los Angeles (UCLA), Crehan might still be in a minimally conscious state. Led by Dr. Martin Monti, the team used ultrasound to jump-start Crehan’s brain in what may prove to be a major breakthrough in the treatment of coma patients and the field of neurosurgery.

“It’s almost as if we were jump-starting the neurons back into function,” Monti, an associate professor of psychology and neurosurgery, said in a written statement.

“Until now, the only way to achieve this was a risky surgical procedure known as deep brain stimulation, in which electrodes are implanted directly inside the thalamus … Our approach directly targets the thalamus but is non-invasive”

The technique, called low-intensity focused ultrasound pulsation, uses a device the size of a coffee cup saucer to create a small sphere of acoustic energy that can be directed at different parts of the brain. In Crehan’s case, the device was placed beside his head and activated for 10 30-second intervals over a 10 minute period.

Prior to the procedure, Crehan only showed minimal signs of consciousness, such as performing minute movements when asked. The day after the procedure, researchers say Crehan’s responses improved greatly. After three days, he had regained full consciousness and language comprehension, nodding his head “yes” and shaking his head “no” to doctors’ questions.

“The change was remarkable,” Monti said.

The technique worked by exciting neurons in the thalamus, an egg-shaped structure in the middle of the brain that serves as the central hub for information processing. While researchers expected the positive result, Monti said that further study on additional patients is needed to determine whether or not the procedure can be used to help more people recover from comas.

“It is possible that we were just very lucky and happened to have stimulated the patient just as he was spontaneously recovering,” Monti said.

Tests on more patients are scheduled for the fall. The team’s initial findings were recently published in Brain Simulation, an academic journal.

The researchers, however, remain optimistic. If the technique is proven to help other coma patients, it could eventually lead to the creation of a portable and low-cost helmet-like device to “wake up” people in vegetative or minimally conscious states. There is currently no effective treatment for such people, Monti said.

Crehan has been resting at home for three months now.

“I’m doing very well,” he says. “I’m still recovering, but I would say I’m above 90 per cent, maybe even like 95 per cent of what I used to be.”

His sense of smell could be gone for good and he still suffers from muddled thoughts and some memory loss, but Crehan says even that is getting better.

“It’s definitely led me to take down a lot more notes than I ever would have done before,” he laughs.

A large scar across his forehead stands as a stark reminder of his February ordeal. But the recent college grad just wants to get on with his life and find a job.

One positive change, Crehan adds, has been his attitude towards life.

“I’m a lot calmer than I used to be,” he says. “I used to have a pretty quick temper, and I don’t even get angry anymore. If something annoying happens, it’s like, ‘Well, I’m not dying from it,’ so it doesn’t really matter.”