For example, this ambitious project may help to unravel the secret of mental illness, which is one of the most debilitating of all human maladies. By mapping the human brain, we might be able to isolate the origin of this affliction. (For example, all of us talk to ourselves silently. When we do, the left brain, which controls language, consults the prefrontal cortex. But in schizophrenics, we now know, the left brain activates without permission from the prefrontal cortex, which is the conscious part of the brain. Since the left brain does not talk to the prefrontal cortex, the schizophrenic thinks the voices in his or her head are real.)