Case Study

This page describes the case study method. The two sections on this page are about the method'spurpose and its advantages & disadvantages.

 

Purpose

The case study is an intense, in-depth investigation of one participant. This participant is called a “case” and can be one person, one animal, or one group. Psychologists will study this case (participant) in great detail, in the hopes of learning things that are generally true.

For example, a famous case study in the field of memory and neuroscience is a man known as H.M. His case was made public in the 1950’s, after he had brain surgery to stop his epileptic seizures. During the operation, his hippocampus was lesioned (damaged). After the surgery, most of his mental processes were the same as before. However, he suffered from a kind of memory problem called anterograde amnesia.

H.M. could not form new long-term memories. He could remember things from before his operation, such as his friends’ names and events in his life. The anterograde amnesia made it impossible for him to learn new things from after the surgery. Even if he spent the day with a new person, he would not remember him or her the next time they met. Events that H.M. went through after his surgery would not be put into his long-term memory. He had to write notes to himself all day long so that he knew what he had eaten for breakfast, that he had already gotten his mail, and so forth.

Psychologists studied H.M. for years. This case demonstrated the effect of hippocampus damage on memory.

Case studies can be of one animal or of one group. For example, researchers interested in jury processes could do a case study of one jury. They would interview each member, videotape the jury’s deliberations, and take other measurements of the jury members’ behaviors.

Advantages

1. One advantage of the case study is that they provide a great amount of description and detail. Researchers can learn a lot from one case. This volume of details suggests many future research questions to follow up in other studies.

2. Another advantage of the case study is that they present opportunities that researchers could not otherwise have. It would be unethical to take a volunteer and damage his or her hippocampus just for the purpose of studying memory effects. However, if a person undergoes surgery or some other event for another purpose, psychologists can study the outcomes. Much of what we know about the human brain comes from case studies of people who have had surgeries or accidents.

Disadvantage

1. The chief disadvantage of the case study is that the results might not generalize to others. In other words, the experiences of one person might not apply to other people. Researchers at the National Zoo are doing case studies with the two pandas (one male, one female). They have a great amount of information on the pandas, but what they find might not be true of all pandas.

With case studies, we learn a lot about one case, but what we learn might not apply to the larger population.