The scientific investigation of basic behavioral processes including sensation, emotion, and motivation, as well as such cognitive processes as perception, memory, learning, problem-solving, and language.
Experimental psychologists work to understand the underlying causes of behavior by studying humans and animals. Animals are studied within and outside laboratory settings for a variety of reasons. A researcher may wish to learn more about a particular species, to study how different species are interrelated, to investigate the evolutionary significance of certain behaviors, or to learn more about human behavior.