Experimental psychology is an approach to psychological research where people use experiments in controlled conditions to explore and test hypotheses about behavior. In addition to using classical experiments, people in this field may also rely on surveys, case studies, and other research methodologies to expand the scope and nature of their work. This discipline originated in Germany in the late 1800s, and examples can be seen all over the world.
In the larger field of psychology, people attempt to understand human behavior, including motivations, human development, and the way people act alone and in crowds. There are numerous branches of psychology covering a variety of topics, from researchers interested in neurology and the brain mechanics behind behavior to researchers following topics like mental illness. In experimental psychology, people set up controlled experimental conditions to test theories.
People can conduct experiments in a wide variety of settings. Researchers may stage a scene on a street or at an event to see how people react if they are interested in social psychology, or could use a controlled lab environment to study isolated behaviors to learn more about development, identity, and abnormal behavior. The experiment is overseen by researchers who log data and look out for the safety of participants, making sure no one is put at undue risk.
This work can involve animal and human subjects. Working with living subjects carries considerable ethical concerns, especially when those subjects are human beings. Some notorious events in the history of experimental psychology led to increased scrutiny of research, with better safeguards to protect subjects. One such example was the 1971 Stanford Prison Experiment, where researcher Philip Zimbardo wanted to explore how people adjust to roles as prisoners and prison guards. The simulation became so real and dangerous for participants that Zimbaro decided to suspend it before it ended, and in advance of a planned “prison break,” where friends of research subjects were planning to end the experiment by force.
When people design studies in experimental psychology, they explore the behavior they are trying to explain and try to create situational controls to isolate and study that behavior. They must be able to demonstrate how a study will contribute to the field of psychology, and must also show safeguards to protect the health and safety of participants. People who want to volunteer for an experimental psychology study must have the capacity for informed consent, understanding the nature of the experiment, their role, and how to opt out.