Placebo Effect

A placebo effect is a phenomenon which may result in some therapeutic effect in subjects given placebo.

Experimental Research

This article is a part of the course "Experimental Research". Enter your email to take the full course.

A placebo is a sham medical intervention that exploits the hope/expectancy-effect to the treatment. It involves giving subject an inert sugar pill, and he/she is told that it may improve the condition, but the person is completely unaware of the fact that it is inert.

In medicine, it has been observed that patient’s belief does indeed sometimes result in therapeutic effect and cause patient’s condition to improve.

Placebo treatment is widely practices in medicine, and it has been recognized to have clinically important effects. A placebo has been defined as a substance or any procedure that is given objectively without any specific activity for the condition being treated.

Indeed, wide variety of things can be considered placebo and do show placebo effect. These may include pharmacological substances like pills, inhalants, creams, injections or even medical devices such as ultrasound, surgery, acupuncture to name few.

In one study, it was observed that patient recovery can be enhanced with positive suggestions and comments by the physician like

“you will certainly be better in few days with this treatment”

and if the patient is given negative words like

“I am not sure that this treatment can work for you”

it negatively affect the recovery of patient.

How it Works?

The placebo effect phenomenon is related to the perception and expectations of the subject. If subject see it helpful, it can heal, and if viewed as harmful, it can cause negative effects or what is known as nocebo effect.

Both expectations and conditioning play an important role in placebo effect and make different kind of contribution.

The expectancy effect is seen to be enhanced through factors like positive attitude of doctor, different in color and size of placebo pills, or use of injections. In one study, researchers found that response to placebo treatment was increased from 44% to 62% when the healthcare professional gave them warmth, attention, and confidence.

Conditioning on the other hand exerts long lasting effects and it seems to affect early stages of information processing. However, as placebo effect is based upon conditioning and expectations of the subject, the effect is seen to disappear if the subject is informed that his/her expectations are unrealistic, or that placebo treatment is completely ineffective.

Despite ongoing controversy concerning use of placebo therapy, there are number of reports showing positive effects of placebo treatment. Placebo seems to work in alleviating pain, anxiety, depression, Parkinson’s disease, arthritis, and even cancer.

Remarkable recovery of “Mr. Wright” from a deadly cancer is just an example of placebo treatment. Placebo effects seems not only be arise from conscious belief but also from subconscious associations between recovery and treatment as researchers has found that placebo effect does arise from active processes in brain.

We would love feedback on this article.
Please let us know about any error.
We highly appreciate suggestions.

Suggest changes

Citation: 

Explorable.com (Mar 22, 2009). Placebo Effect. Retrieved Jan 03, 2014 from Explorable.com: http://explorable.com/placebo-effect