Some physicians believe that the application of electricity to deep areas of the brain can bring individuals out of so-called irreversible comas. Orthopedic surgeon Edwin Cooper accidentally discovered that electrical stimulation had an arousal effect on severely brain-injured patients. At the time, he was using a neuro-stimulator to relieve spasticity in the limbs of microephalics. These patients have small skulls, reduced brain capacity, and poor control of their muscles. During this treatment, one of his patients began to look around the room, smiling at people, rather than staring blankly. Cooper already knew that placing a stimulator in one arm of a paraplegic to strengthen it also made the other arm stronger. Cooper hypothesized that similar stimulation could help wake up people in comas. He began experiments in 1993. The results Cooper has obtained indicate that patients who are given electrical stimulation come out of their comas sooner and regain their functions more quickly than those who receive traditional treatment. No one knows exactly why electrical stimulation works, but there is evidence that is has major effects on the brain. Critics of Cooper's experiments say that using electrical stimulation to treat patients in vegetative states is 'junk science.' Any apparent success Cooper has had with patients was obtained because those patients were minimally conscious and not in a vegetative state to begin with.