Researchers in France say they were able to restore signs of consciousness from a 35-year-old brain-injured man who has spent the last 15 years in a coma after a fatal car accident.
He showed such signs, reports say, after undergoing a groundbreaking therapy that involves stimulation of the vagus nerve.
Vagus Nerve Stimulation
Vagus nerve stimulation is sometimes used for depression or for reducing the number of seizures in an epilepsy. The vagus nerve serves many roles in the anatomy: it controls the slowing of the heartbeat and the muscles of the small intestine.
The patient has stayed in a vegetative state since the car accident occurred, lying unaware of his surroundings, but when the researchers fitted implant to his chest that can stimulate the vagus nerve, the man seemed to be in a state of partial consciousness, as The Guardian reports.
What A Coma Patient Was Able To Do After Vagus Nerve Stimulation
The patient started tracking objects with his eyes, and he was also able to stay awake as another person read him a story, and once he even opened his eyes in surprise when an examiner suddenly moved her face closer to the patient's. What's more, he was able to respond to basic requests such as turning his head when asked, despite this taking a minute to achieve.
The man was also able to shed a tear and smile when his favorite song played. This could have been the result of the simulation performed. According to Angela Sirigu, from the Marc Jeannerod Institute of Cognitive Science in France, brain damage prevented the man from speaking.
"He is still paralysed, he cannot talk, but he can respond. Now he is more aware."
Sirigu is one of the many authors of a study aptly called "Restoring consciousness with vagus nerve stimulation," published by the Current Biology Monday, Sept. 25.
The researchers were able to record major changes in the man's brain activity after the stimulation was performed, including signs pointing to increased electrical communication between different regions of the brain and increased activity in areas associated with awareness, movement, and sensation.
The patient started showing signs of consciousness about a month after the implant was switched on. This persisted up to five months of stimulation, said Sirigu.
"Our study demonstrates the therapeutic potential of vagus nerve stimulation to modulate large-scale human brain activity and alleviate disorders of consciousness," said the authors.
Over the past decade, scientists and researchers have had major breakthroughs in communicating with "locked in" patients, employing various types of brain-to-computer interfaces. These advances have allowed paralyzed patients, some of whom believed to be in vegetative states, to respond "yes" or "no" to basic questions.