What is the purpose of this experimental structure? A researcher conducted an experiment on the effects of a new “drug” on depression. The researcher had a control group that received nothing,...

What is the purpose of this experimental structure? A researcher conducted an experiment on the effects of a new “drug” on depression. The researcher had a control group that received nothing, a placebo group, and an experimental group that received the “drug.”

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kipling2448 eNotes educator| Certified Educator

The experiment, common in the pharmaceutical world, involves three separate groups of people, one that will be administered the experimental drug, another that will receive a placebo, and a third that will be given neither. The purpose of this structure is to determine, to the extent possible, the actual effectiveness of the real drug on individuals suffering from depression. The group that will be given neither the real medication nor the placebo, a fake pill that the control group in question will be told is the real drug, represents the untreated population of those who have been diagnosed with some form of depression. The group that receives the real drug will be closely monitored for its aggregate reaction to the medication.

As depression involves, in many cases, the physical structure of the human brain, including the manner in which certain chemicals are produced, then a medication designed to address depression in an individual may manipulate those functions of the brain, such as spurring increased or decreased production of the chemicals in question. Other causes of depression may involve physical trauma, the suddenness of a major, tragic event such as a death in the family or a diagnosis of a major illness, or an adverse side-effect of a medication intended to address an unrelated issue.

With multiple possible causes of depression, and with the physical structure of the individual brain being so complex and involving so many chemical reactions, tests designed to determine the effectiveness of a drug to treat depression include many variables, including the known phenomenon in which individuals convince themselves that a “drug” is having the desired effect even though the “drug” they have been given is actually a placebo.

The so-called “placebo effect” is an integral part of experiments designed to effect depression precisely because depression is a mental health issue that may or may not involve physical causes such as the structure of the individual limbic system and its components. Emotional responses to external stimuli, for example, can be manipulated through the administration of actual medications or other types of drugs, or those responses can manipulated by convincing test subjects of the authenticity of the fake medications they have been given as part of a placebo control group.

In many cases, if people believe that they are taking the actual medication, then they convince themselves that they are responding positively to that medication despite the fact that they may be receiving a placebo. In other words, they believe they are getting better, so they actually feel better even though there has been no interaction of man-made pharmaceuticals with their neurologic systems. It’s all rather complicated, but the “placebo effect” is real, so it must be taken into account when new medications designed to address depression are tested. If a statistically-significant percentage of the placebo control group responds positively to the fake drug its members have been given, then the results of the tests involving the group that has been given the real drug may be invalid.