The Little Albert experiment was a controlled experiment showing empirical evidence of classical conditioning in humans. The study also provides an example of stimulus generalization. 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.
After observing children in the field, Watson hypothesized that the fearful response of children to loud noises is an innate unconditioned response. He wanted to test the notion that by following the principles of the procedure now known as "classical conditioning", he could use this unconditioned response to condition a child to fear a distinctive stimulus that normally would not be feared by a child (in this case, furry objects).
The aim of Watson and Rayner was to condition a phobia in an emotionally stable child. For this study they chose a nine-month old infant from a hospital referred to as "Albert" for the experiment. Watson followed the procedures which Pavlov had used in his experiments with dogs.
Before the experiment, Albert was given a battery of baseline emotional tests: the infant was exposed, briefly and for the first time, to a white rat, a rabbit, a dog, a monkey, masks (with and without hair), cotton, wool, burning newspapers, and other stimuli. Albert showed no fear of any of these items during the baseline tests.
For the experiment proper, Albert was put on a mattress on a table in the middle of a room. A white laboratory rat was placed near Albert and he was allowed to play with it. At this point, Watson and Rayner made a loud sound behind Albert's back by striking a suspended steel bar with a hammer each time the baby touched the rat. Albert responded to the noise by crying and showing fear. After several such pairings of the two stimuli, Albert was presented with only the rat. Upon seeing the rat, Albert got very distressed, crying and crawling away. Apparently, the infant associated the white rat with the noise. The rat, originally a neutral stimulus, had become a conditioned stimulus, and it was eliciting an emotional response (conditioned response) similar to the distress (unconditioned response) originally given to the noise (unconditioned stimulus).
In further experiments, Little Albert seemed to generalize his response to the white rat. He became distressed at the sight of several other furry objects, such as a rabbit, a furry dog, and a seal-skin coat, and even a Santa Claus mask with white cotton balls in the beard. However, this stimulus generalization did not extend to everything with hair.
It should be noted that Watson's experiment had many failings by modern standards. For example, it had only a single subject and no control subjects. Furthermore, such an experiment could be hard to conduct in compliance with current law and regulations, given the expected risks to the subject.
Albert was about one year old at the end of the experiment, and he reportedly left the hospital shortly thereafter. Though Watson had discussed what might be done to remove Albert's conditioned fears, he had no time to attempt such desensitization with Albert, and it is likely that the infant's fear of furry things continued post-experimentally.
Watson later gave a series of weekend lectures describing the Little Albert study. One of these lectures was attended by Mary Cover Jones, which sparked her interest in pursuing graduate work in psychology. She became known as the "Mother of Behavior Therapy" following a study she conducted on a three-year-old.
According to some textbooks, Albert's mother worked in the same building as Watson and didn't know the tests were being conducted. When she found out, she took Albert and moved away, letting no one know where they were going. A 2009 report, however, disputes that. The original report had stated that the baby's mother was a wet nurse at the hospital, who may have felt coerced and unable to turn down a request for her baby to be used in Watson's experiment.
In 2009, psychologists Hall P. Beck and Sharman Levinson published an article in which they claimed to have discovered the true identity of "Albert B." After reviewing Watson's correspondence and publications, as well as research in public documents (such as the 1920 United States Census and state birth and death records), Beck argued that "Albert B." was a pseudonym for Douglas Merritte, the son of Arvilla Merritte, then a woman who appears to have been a wet nurse at the Harriet Lane Home. Recent research has shown, however, that Douglas Merritte may not have been "Little Albert", who may in fact have been young William Barger.
The identity claimed by Beck, Levinson, and Irons has been contested by psychology researchers, Russ Powell and Nancy Digdon, as well as Watson scholar, Ben Harris, who offer an alternative identity based on available data. William Barger had been born within a day of Merritte, was known by friends and family as "Albert" (even though his given name was William), and his mother had also worked at the hospital where the experiment was conducted. In addition, his size and developmental condition much more closely matched the experiment's documentation of the subject baby's condition. Through the use of a professional genealogist, the researchers learned Barger had died in 2007 at age 87 and identified one close living relative, a niece. In an interview, Barger's niece stated that she and her uncle had been quite close throughout his life, acknowledged Barger's antipathy toward dogs as a well-known fact that family members would tease him about (the researchers noted there was no way to determine whether or not this behavior was linked to Watson's experiment), and stated that she did not recall any other phobias. The researchers concluded that Barger would have been unaware of his role as an infant test subject.
Although he probably continued to fear various furry objects for a time, he would likely have been desensitized by his natural environments later in life. Nonetheless, the experiment today would be considered unethical according to the American Psychological Association's ethic code, and legislation has been passed to prevent such potentially harmful experiments. In the early 1970s, following widely publicized cases of research abuse, The National Commission for the Protection of Human Subjects of Biomedical and Behavioral Research (NCPHS) was created to study issues surrounding the protection of humans in research. In 1979, the Commission issued a report entitled Ethical Principles and Guidelines for the Protection of Human Subjects of Research (commonly called the Belmont Report), which provided the ethical framework on which current federal regulations for the protection of human participants in research are based. Under the NCPHS standards set in the late 1970s, an experiment such as Watson's would not have been allowed. There are also regulations now put in place by the Health Insurance Portability and Accountability Act of 1996 and the Public Health Service Act, as well as required education since 2000 in the use of human research participants required by the National Institutes of Health.
A detailed review of the original study and its subsequent interpretations by Ben Harris (1979) stated:
Critical reading of Watson and Rayner's (1920) report reveals little evidence either that Albert developed a rat phobia or even that animals consistently evoked his fear (or anxiety) during Watson and Rayner's experiment. It may be useful for modern learning theorists to see how the Albert study prompted subsequent research [...] but it seems time, finally, to place the Watson and Rayner data in the category of "interesting but uninterpretable" results.
It is difficult to be certain exactly what happened during the Little Albert Experiment since concrete evidence and scientific records are lacking. Though a film was shot during the experiment, textbooks interpret the movie differently. Various sources give contradicting accounts of events that took place, and they raise questions about exactly what stimuli were used, which stimuli the baby came to fear, and what happened to the child after the experiment. It was said that most textbooks "suffer from inaccuracies of various degrees" while referring to Watson and Rayner's study. Texts often misrepresent, exaggerate, or minimize the range of Albert's post-conditioning fears.
Other criticisms stem from the health of the child (cited as Douglas Merritte) who was not a "healthy," "normal" infant as claimed in the study, but one who was very ill and had exhibited symptoms of hydrocephalus since birth--according to relatives he never learned to walk or talk later in life. The child would die five years after the experiment due to complications from the congenital disease. It is stated that the study's authors were aware of the child's severe cognitive deficit, abnormal behavior, and unusually frequent crying, but continued to terrify the sick infant and generalize their findings to healthy infants, an act criticized as academic fraud. These accusations have been challenged in another academic article which states that the child was actually William (called Albert by his family) Barger, and that the child was, in fact, healthy.