Summary
Highlights
The scientific method is a systematic process used in psychology to understand the mind and behavior. It begins with forming a theory based on observations, then developing a testable hypothesis. For instance, if the theory is that sleep boosts memory, a hypothesis could be that sleep-deprived people remember less. The next step is to design a study and collect data, ensuring operational definitions specify how variables like 'sleep-deprived' are measured. Data analysis determines statistical significance, leading to confirmation, rejection, or revision of the theory. Finally, findings are published to allow replication and bias checks, emphasizing why psychology is considered a science.
Another example of the research process investigates the theory that low self-esteem feeds depression. A hypothesis would be: people with low self-esteem score higher on a depression scale. This type of research often uses assessments to measure subjective experiences like self-esteem and depression. This is an example of correlational research, which observes relationships between variables. The research process is cyclical; initial findings might lead to refining the hypothesis or gathering more data, continuously seeking to clarify cause-and-effect relationships and explore potential third variables.
Descriptive studies provide information for further testing but do not establish cause and effect. Three types include: Case studies, which involve in-depth analysis of one or a few individuals to generate hypotheses; for example, the study of 'HM' revealed the hippocampus's role in new memory formation. Surveys quickly gather information on attitudes and opinions but can be biased by wording and social desirability. Naturalistic observations involve observing subjects in their natural environment without intervention to avoid altered behavior, like Jane Goodall's chimpanzee studies. These methods serve as a foundation for more rigorous research.
To be considered a science, psychology must move beyond observation to experimental research. Experiments vary one or more factors (independent variables) to observe their effect on behavior or mental processes (dependent variables), while controlling for other factors. The independent variable is manipulated by the experimenter, while the dependent variable is the outcome measured. Participants are randomly assigned to either an experimental group (exposed to the independent variable) or a control group (not exposed), ensuring a fair comparison and allowing for the determination of cause and effect.
An experiment investigating whether texting while driving is dangerous defines texting as the independent variable and the number of cones hit as the dependent variable. An experimental group texts while driving an obstacle course, following strict operational definitions for texting. A control group drives the same course without texting. Random assignment ensures individual differences (like driving skill) are evenly distributed between groups. The expected outcome is that the texting group will hit more cones, confirming the theory that texting while driving is dangerous.
Another experiment tests if aerobic exercise reduces anxiety. Aerobic exercise (e.g., 30 minutes of cardio three times a week for a month) is the independent variable, with clear operational definitions. Anxiety levels, measured before and after the study, are the dependent variable. Participants are randomly assigned to an experimental group (exercising) or a control group (no prescribed exercise). The goal is to see if the experimental group's anxiety levels decrease significantly more than the control group's. Random assignment helps mitigate confounding factors, allowing for causal conclusions about the exercise's effect on anxiety.