The Placebo Effect

This week in class, we learned about the different types of observation and experimentation. These methods are the basis of all scientific study. Experimentation is the only method of scientific manipulation that can help determine whether one variable causes another. Observation merely observes and documents what naturally happens. In experimentation, the researchers control for as many variables as possible. They leave one variable as the independent variable and manipulate it in order to record what happens to the dependent variable. Additionally, when subjects are selected to take part in the experiment, they are divided into two groups: the experimental group and the control group. The control group is the group used to measure the norms for the dependent variable when the independent variable is not manipulated. The experimental group is the group in which the experiment actually happens; the independent variable is manipulated and the dependent variable is effected. This split is done randomly, also known as random assignment. Random assignment is done so as to eliminate the influence of any confounding variables, such as age, gender, IQ, socio-economic status, and race. Once this is done, the experiment can be administered.

We also learned in class that experimenter bias can have a huge impact on the outcome of the experiment. If the experimenter told the people in the control group to drink their water, the control group would know that they're not receiving the vodka and be confused. If the experimenter told the experimental group to drink the vodka, then the experimental group would try to guess what the experimenters want to see and act accordingly. This is called demand characteristic. To prevent any of this confusion, experiments are conducted using the double-blind method. In the vodka-water experiment, both groups would receive covered cups so that they would not be able to tell which substance they would be drinking. Furthermore, the water would be laced with vodka so that it at least smelled like the real drink. Most importantly, the experimenters don't know what substance they are giving to the people and cannot subconsciously influence how the people act. Double-blind is the ideal method, although single-blind (method) procedures are conducted. In single-blinds, the researcher knows what he's giving but the subject doesn't know what he/she is receiving.

Hypothetically, what would happen if a researcher told a person in the control group that, "this medicine works wonders?" The person would immediately think that they are part of the experimental group and alter their behavior so that it seems like the medicine is working. Their behavior might change, but their bodies might react to simply thinking that the medicine is working. It has been scientifically proven that thinking you are receiving a substance will make your body react to the phantom substance. How cool is that? Naturally, this often skews the control group's results, so it has to be eliminated as a confounding variable. By the way, this is called the placebo effect.

If anyone has ever seen "Harry Potter and the Half-Blood Prince" and watched the first Quidditch match, you will know that Harry used the placebo effect on Ron. Ron was nervous and didn't even want to play the game. Harry pretended to slip some Felix Felicis (liquid luck potion) into Ron's pumpkin juice. Once Ron thought he had drunk the potion, he acted as if he had. When Hermione, who also thought that Harry had slipped the potion into Ron's drink, confronted him about the illegality of his actions, Harry showed her that he had only pretended to add the potion.

I find it amazing that the human mind can be capable of this. Just thinking that you have done something that will help your performance is enough to make your performance as good as it would have been had you taken the substance. Fascinating. Since our study of AP Psychology is still in its infancy, I look forward to more fascinating truths about how the brain works.

Here's the video link in case anyone was interested. Funny enough, the top comment reads, "Power of PLACEBO."

 http://www.youtube.com/watch?v=J0BUXUXceHQ