Scientists at the French National Center for Scientific Research have used nerve stimulation to induce signs of consciousness in a man who has been in a vegetative state for the last 15 years.
The vagus nerve connects the brain to the gut, along with other parts of the body. It’s also known to have a role in the process of waking from sleep, and in keeping us alert. Thus, Dr Angela Sirigu thought it could play a role in restoring consciousness to patients with unresponsive wakefulness syndrome.
In surgery lasting about 20 minutes, a small implant was placed around the vagus nerve in the 35-year-old man’s neck. After one month of vagal nerve stimulation, the patient’s attention, movements and brain activity significantly improved and he had shifted into a state of minimal consciousness.
Traditionally, the longer a person is in a vegetative state, the less likely they are to recover. But this breakthrough demonstrates consciousness can be restored after a much longer time. The treatment challenges a widely-accepted view that there is no prospect of a patient recovering consciousness if they have been in a persistent vegetative state for longer than 12 months.
“The chosen individual had a car accident at the age of 20, and remained unresponsive 15 years later. After a month of stimulation of the vagus nerve with a current of around a milliamp, the man was able to turn his head on request. His eyes could follow a moving object and he appeared to stay awake longer when read to. He also spontaneously opened his eyes wider when someone’s head rapidly approached his face.”
Moreover, it was particularly emotional for the patient when tears dropped from his eyes as he was listening to the music from one of his favorite singers Jean Jacques Goldman.
Sirigu, who led the work at the Institut des Sciences Cognitives Marc Jeannerod in Lyon, France, said: “He is still paralysed, he cannot talk, but he can respond. Now he is more aware.”
Sirigu says her team is going to follow the same procedure on patients with less damage. “Brain plasticity and brain repair are still possible even when hope seems to have vanished.“