After being in a vegetative state for 15 years, scientists have managed to restore a man’s brain activity.
Scientists have managed to induce signs of consciousness in a person who has remained in a vegetative state for most of his life. While the individual is yet to return to consciousness, his case proves that brain activity can be restored after a much longer time than previously proved.
According to established scientific wisdom, the longer a person is in a vegetative state, the less likely they are to recover. But according to one doctor, a single nerve may be the key. The vagus nerve primarily connects the brain to the stomach, but it also helps us wake up. The nerve also releases the hormone Norepinephrine, which enables the sharing of information between different regions of the brain.
Dr Angela Sirigu hypothesised that the nerve could also restore consciousness in those suffering from unresponsive wakefulness syndrome. To prove it, Sirigu sought the patient who had gone the longest without improvement.
As IFLScience noted, “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.”
Sirigu reported in Current Biology “that electroencephalogram (EEGs) also showed increased brain activity, including in the theta waves used to define the differences between states of consciousness. Metabolic activity was found to have increased in the cortex and sub-cortex, indicating a need for more fuel among brain cells.”
These tests led doctors to upgrade the patient’s status from unresponsive to “minimal consciousness”, and Sirigu to conclude in a statement: “Brain plasticity and brain repair are still possible even when hope seems to have vanished.”
As it goes, if an individual has been vegetative for a year is unlikely to show progress, and after 15, it is even rarer.
Sirigu hopes that their observations provide insight into where consciousness lies within the brain.
The work, they write, identifies the parietal cortex as “a major player in guiding the expansion of neural activity across brain regions”, promoting further study on this part of the brain.