In the Little Albert experiment, researchers used a white rat to condition an infant’s fear.
John B. Watson and Rosalie Rayner conducted the study at Johns Hopkins University in 1920. They presented an infant, known as “Little Albert,” with a white rat and other furry objects. At first, the child showed little fear of the rat. The researchers then paired the rat with a loud, startling noise. After repeated pairings, Albert reportedly began crying and withdrawing when the rat appeared, even without the noise.
The experiment became a famous example of classical conditioning in humans: a previously neutral object was associated with an unpleasant stimulus and came to produce a fear response. Later accounts suggest that Albert’s fear generalized to other furry items, including a rabbit and a fur coat.
The study is now widely criticized because of its small sample, limited controls, incomplete follow-up, and serious ethical problems. Researchers did not clearly remove the conditioned fear before Albert left the study.