Experimental Psychology and the Scientific Method

Experimental Psychology and the Scientific Method

• Psychology is the study of behavior and mental processes
• Psychological research relies on scientific methodology
• Commonsense psychology is often nonscientific and prone to errors (e.g., Friday the 13th)
• Psychological science shares key features with all modern science, including:
  • Gathering observable, objective data
  • Seeking general laws or theories to explain relationships among data

Science Overview

• Science is the systematic collection of data to describe events under specific conditions
• Science aids in organizing, categorizing, and understanding the universe
• The Latin word "scientia" means "knowledge"
• Methodology is a basic tactic in psychological research, encompassing scientific techniques for collecting and evaluating data

Experimental Psychology

• Experimental psychology is a methodological approach, not a subject, encompassing diverse areas within psychology
• Experimental psychology uses scientific methods to research the mind and behavior
• Four primary objectives of psychological science:
  • Description
  • Prediction
  • Explanation
  • Control

Tools of Experimental Psychology

• Observation: Systematic noting and recording of observable events; non-observable events are studied through defining them in terms of observable events
• Measurement: Determining dimensions (height, width, etc.) of events or behaviors; standards are used to ensure accuracy

Experimentation

• Experimentation is a process to discover new things or demonstrate existing event patterns under specific conditions through the systematic manipulation of aspects of the setting
• Two fundamental requirements for experimentation:
  • Procedures to manipulate the setting
  • Observable predicted outcome (testable)

Additional Research Methods

• Good Thinking: Using logic and rational analysis to collect and interpret data
• Replication: Repeating procedures to ensure consistent results; objective observations, measurements, and good thinking are crucial

Conducting Experiments

• Requirements:
  • Testable hypothesis
  • Observable predicted outcome
  • Measurable outcome

Explanations

• In science, explanations specify antecedent conditions (circumstances occurring before an event or behavior)
• Psychology includes conditions like food deprivation or childhood experiences as antecedent conditions

Psychology Experiments

• Psychology experiments create specific sets of antecedents (treatments)
• Psychology experiments are controlled procedures using at least two different treatment conditions for research subjects

Experimental Procedures

• Subjects' behaviors are measured and compared to test hypotheses about the effects of treatments
• The procedures of psychological experiments must be carefully controlled, maximizing accuracy of measurements

Cause-and-Effect

• Cause-and-effect relationships can be inferred between treatment conditions and subject behaviors
• Treatments can be considered as the cause of observed behaviors

History of Experimental Psychology

• Wilhelm Wundt started the field of psychology in 1879 in Leipzig, Germany with a psychology lab
• G. Stanley Hall initiated the first experimental psychology lab in the U.S. in 1883 at John Hopkins University
• James McKeen Cattell opened the third experimental psychology lab in 1887 at University of Pennsylvania
• Mary Whiton Calkins established an experimental psychology lab in 1891 at Wellesley College, becoming the first woman to establish a psychology lab
• In 1893, G. Stanley Hall established the American Psychological Association (APA)

Notable Experiments

• In 1920, John and Rosalie Raynor and their Little Albert experiment investigated the classical conditioning of emotional reactions in people
• In 1961, Albert Bandura led the Bobo Doll experiment, exploring the impact of observation on aggressive behavior

The Research Process

• A scientific approach starts with reviewing existing research to form a hypothesis about behavior.
• Procedures to test these hypotheses are designed.
• Data is analyzed using statistical methods to support or reject the hypothesis.
• A research report outlining methods and findings is written, providing insights to the field.