At a time when psychology was trying to establish itself as a rigorous science, researchers were increasingly drawn to experiments that could demonstrate clear, observable laws of behaviour. One of the most influential ideas came from Ivan Pavlov, whose work with dogs had shown that animals could be trained to associate a neutral stimulus, like a bell, with food, eventually responding to the sound alone.The question that followed was direct and ambitious: if animals could be conditioned in this way, could human emotions be shaped through the same process?That question drove the experiment conducted between 1919 and 1920 at Johns Hopkins University by John B. Watson and his graduate student Rosalie Rayner. Their aim was to provide experimental evidence that emotional responses in humans, particularly fear, could be learned through conditioning, rather than inherited or instinctive. The researchers conducted the study on an infant who could not consent, using methods that would later be considered ethically questionable: the researchers deliberately provoked fear by exposing the infant to a white rat and other stimuli, pairing each encounter with loud, frightening noises. Distress was induced without any measures to alleviate fear, and there were no follow-up procedures to remove the conditioned response. By today’s standards, the experiment is widely condemned. Intentionally causing harm to a vulnerable infant makes it one of the darkest and most infamous episodes in the history of psychological research, highlighting the ethical limits of experimentation on human subject
Why “Little Albert” was chosen
The subject of the study was a nine-month-old boy, referred to as “Little Albert.” Watson and Rayner selected him deliberately. According to their published account, he was “healthy from birth,” weighing approximately 21 pounds at nine months, and had an unusually calm temperament. He was described as “stolid and unemotional,” rarely crying and showing little fear or distress in everyday situations. Albert had been raised in a hospital setting because his mother worked as a wet nurse at the Harriet Lane Home for Invalid Children, part of Johns Hopkins. This environment allowed researchers controlled access to observe and test him over time. This stability was central to the experiment. The researchers wanted a child who did not already display strong fear responses, so that any emotional reaction could be clearly linked to the conditioning process rather than prior temperament.
Establishing a baseline: no fear, only curiosity
Before any conditioning began, the researchers conducted baseline tests, Watson and Rayner exposed Albert to a series of objects and animals to observe his natural reactions. These included a white rat, a rabbit, a dog, a monkey, masks (with and without hair), cotton wool, and even burning newspapers. Albert showed no fear. He reached out, touched the objects, and appeared curious. Observations from his mother and hospital staff supported this, noting that he rarely cried and had not shown fear or anger in daily life.
Before conditioning, the infant showed no fear toward animals, objects, masks, cotton wool, or burning newspapers/ Youtube
The only stimulus that reliably produced distress was a sudden, loud noise, created by striking a steel bar behind his head. On the first occurrence, Albert startled. On subsequent strikes, his lips trembled and he began to cry. This response became the unconditioned stimulus the researchers would use.
Conditioning fear: pairing a rat with a shock
The key phase of the experiment began when Albert was around 11 months old. A white rat was placed near him. As he reached out to touch it, the researchers struck the steel bar behind his head.The pairing was repeated across sessions. In the first session, he startled and buried his face but did not cry immediately. In the second session, conducted about a week later, the reaction intensified. After several pairings, the rat alone began to provoke hesitation. When it brushed his hand, he withdrew sharply.After five pairings of rat and noise, the change was evident. When shown the rat without any accompanying sound, Albert reacted with visible distress, his face puckered, he whimpered, turned away, and began to cry. On one occasion, he attempted to crawl away so quickly that he had to be caught before reaching the edge of the table.
The Little Albert Experiment demonstrated that classical conditioning could be used to create a phobia. A phobia is an irrational fear, that is out of proportion to the danger/ Image: Simply Psychology
Between trials, he was given wooden blocks and played calmly, smiling and interacting as before. This contrast was important for the researchers, as it suggested the fear response was tied specifically to the conditioned stimulus.
Fear spreads beyond the original trigger
The researchers then tested whether Albert’s fear would extend to similar objects, a process known as generalisation.It did. When presented with a rabbit, he leaned away and cried when it touched him. A dog initially caused him to shrink back, and when it approached his face, he began to cry. A fur coat led to immediate withdrawal and distress. Cotton wool was avoided, though he interacted with its paper wrapper. A Santa Claus mask with white hair triggered crying and attempts to turn away. Even the hair of the experimenters provoked discomfort.These responses indicated that the learned fear was not limited to the original object but had spread to other stimuli with similar textures and appearances.
The researchers also tested Albert in a different setting, a large lecture hall rather than the smaller room used previously. Some responses appeared less intense, but the fear remained present. When a dog barked suddenly near him, he fell over and cried loudly.
A final visit: the one-month follow-up
Approximately 31 days after the conditioning sessions, Watson and Rayner returned to observe Albert again. His reactions had changed in intensity but had not disappeared. When shown the rat, he no longer cried as strongly, but he avoided it, showed visible unease, and engaged in thumb-sucking, a behaviour interpreted as self-soothing. The researchers had planned to carry out “deconditioning” procedures to remove the learned fear. However, Albert’s mother withdrew him from the hospital on the same day, and the experiment ended without any attempt to reverse the conditioning.
The unresolved identity of “Little Albert”
For decades, the identity of the child remained unknown. Two main candidates have been proposed.One theory, advanced by psychologist Hall Beck, identified Albert as Douglas Merritte, the son of a wet nurse at Johns Hopkins. Merritte died at age six from complications related to hydrocephalus. Some later analyses suggested the child in the experiment may have shown signs of neurological impairment, raising concerns that Watson misrepresented his subject.A later and widely cited alternative, proposed by Russ Powell and colleagues, identified Albert as William Albert Barger. Records showed a close match: his name (“Albert B.”), age at discharge (1 year and 21 days, matching Watson’s report), and physical condition, a healthy, “chubby” infant weighing around 21 pounds at nine months.If Barger was indeed the child, he lived until 2007. His niece later recalled that he had a lifelong aversion to animals, though no direct causal link to the experiment has been established.
Why the experiment remains deeply controversial
Even by the standards of its time, the study raised concerns. By modern ethical frameworks, it would not be permitted.Albert could not consent. His distress was deliberately induced. The fear was not removed. And questions remain about whether his condition was accurately reported.The experiment did demonstrate a foundational idea in psychology: that emotional responses can be learned through association, much like the conditioning observed earlier by Ivan Pavlov in animals.But it also exposed the risks of treating human subjects, especially children, as instruments of proof. The findings endure in textbooks. So does the unease about how they were obtained. Go to Source

