At the heart of medicine's placebo effect is the brain's ability to think away symptoms and concoct

treatment out of belief. And until now, researchers have been able to achieve this only by misleading

subjects--telling them that a fake pill is a real one. But a new study from Harvard Medical School

suggests that the placebo effect may work even if patients are entirely aware of what they're taking.

When a group of patients with irritable-bowel syndrome (IBS) were told they were taking a completely

inert substance that would reduce their symptoms "via a mind-body self-healing process," 59% reported

feeling better, compared with 35% of a similar group who received no treatment at all. Other work showed that patients who believe they will benefit from a placebo show more activity in regions of the

brain associated with the anticipation of pleasure and the dulling of pain.

Tapping into these neurological networks may be a way to help those suffering from disorders beyond

IBS, providing real relief with no real chemistry. And the latest data hint that it may be possible to do this

even when the last bit of trickery the Harvard team used--acknowledging that the pill was a placebo but

telling the patients it would work--is left out.