Schizophrenia (split personality) is the most mysterious, and perhaps the commonest, of mental disorders. It is hard to diagnose, hard to treat, and it accounts for at least 35% of U.S. insane-asylum inmates.
Psychiatrists would like to have some sure method of telling whether a patient is schizophrenic—and whether treatment is doing him any good. Dr. Robert G. Grenell, at Yale University's department of neuroanatomy, added a new idea to an old gadget, evolved a technique that he hopes will answer both questions.
The presence of electricity in animal brains has been known since 1874;...