One of the most
puzzling facts of medicine is the placebo effect: namely, that a substantial
proportion of patients report feeling better after receiving a "sugar
pill," or some other treatment with no known benefit for their illness.
Between 30 - 60% of patients with illnesses ranging from
arthritis to depression
report a substantial improvement in their symptoms after
receiving a placebo. It is not clear that placebo
can "cure" any illness, but the power of the placebo effect
in improving symptoms and reducing suffering is impressive.
Our research program is designed to help us understand how
occur and how to distinguish between people who are
exhibiting a placebo response
and those responding to the specific treatment (e.g. medication).
Our group is the first to report that when treatment with
placebo reduces symptoms,
it also changes the function of the brain. We examined
research subjects with major depression,
some of whom respond favorably to placebo treatment as part
of research studies. When
the subjects improved during placebo treatment, their brain
function changed; the changes
seen during placebo treatment were different from those
seen during medication treatment.
You can read the press release here and
the full article was published online
in January 2002 in the American Journal of Psychiatry.
This work was replicated and extended in our December 2004
publication in Psychopharmacology.
More recently, we have reported that brain function changes during
a brief placebo treatment period can identify those who will later
develop side effects when taking a real antidepressant medication.
The press release and article from
the April 2005 issue of Neuropsychopharmacology
are both online.