He had entered a state of minimal consciousness. The man could follow an object with his eyes and turn his head upon request. The vagus nerve links the brain to the larynx, pharynx, heart, lungs, gut, and other parts of the body. It plays an important role in alertness and waking, The treatment already in use for epilepsy and depression and proved to work even if the general belief is that disorders of consciousness that persist for longer than 12 months are irreversible.
Improvements in scores of a test called the Recovery Scale-Revised (CRS-R) test were observed. A theta EEG signal important for distinguishing between a vegetative and minimally conscious state increased significantly in areas of the brain involved in movement, sensation, and awareness. VNS also increased the brain’s functional connectivity. A PET scan showed increases in metabolic activity in both cortical and subcortical regions of the brain, too. “Brain plasticity and brain repair are still possible even when hope seems to have vanished,” said Angela Sirigu of Institut des Sciences Cognitives Marc Jeannerod in Lyon, France.