Learning from Switched-Off Brains; January 2004; Scientific American Mind; by Claus C. Hilgetag; 2 Page(s)

It may seem bizarre to simulate brain damage in a healthy person with a "virtual lesion" - even when the effect is temporary and painless. But tests that use magnetic fields to deactivate selected areas of the brain show that the technique can vastly contribute to our understanding of that organ's function.

More than that, transcranial magnetic stimulation (TMS), as the approach is called, may someday be used to relieve a variety of disorders caused by malfunctioning neural circuits. For example, the U.S. Food and Drug Administration is investigating TMS as a treatment for depression; the practice is already permitted in Canada. Other potential therapeutic targets include obsessive-compulsive disorder, schizophrenia, Parkinson's disease, dystonia (involuntary muscle contractions), chronic pain and epilepsy. In addition to treatments for damaged brains, recent studies suggest that TMS may be used to improve normal ones, by temporarily enhancing cognition.