The Little Albert experiment was a study that mid-20th century psychologists interpret as evidence of classical conditioning in humans. The study is also claimed to be an example of stimulus generalization although reading the research report shows that fear did not generalize by color or tactile qualities. It was carried out by John B. Watson and his graduate student, Rosalie Rayner, at Johns Hopkins University. The results were first published in the February 1920 issue of the Journal of Experimental Psychology.

Classical conditioning is a behavioral procedure in which a biologically potent stimulus is paired with a neutral stimulus. The term classical conditioning refers to the process of an automatic, conditioned response that is paired with a specific stimulus.