Improving with Placebos
Recent study results help explain the so-called "placebo effect," in which people who take sugar pills during clinical trials often show some improvement. Participants in a recent study showed brain responses both to depression medication and to placebos (sugar pills), but the responses were actually quite different.
In the study, 51 participants took either antidepressant medications or a placebo. They then underwent brain imaging tests, which revealed changes in the prefrontal cortex, the area of the brain associated with mood regulation.
Interestingly, people taking antidepressants experienced brain changes within 48 hours, and the change related to a decrease in activity in that area. For placebo takers, it took two weeks for the change to become noticeable, and the change was an increase in activity.
At eight weeks, participants experienced improved moods, whether they were taking actual medication or placebo. Than, when participants taking placebos were told they were not actually on medication, most of them experienced a deterioration of mood. Many of these patients ended up taking actual antidepressants.
Study researchers speculate that simply the act of going and getting some kind of treatment may be as important a step as taking the drug itself.
American Journal of Psychiatry, 1 January 2002.