2.2 Classical conditioning
Ivan Pavlov (1849–1936) was a Russian neurophysiologist who studied the physiology of digestion. During this research he noticed that hungry dogs would salivate at the mere sight of the attendant who brought the food. He used this seemingly minor observation to develop his theory of classical conditioning (see Box 2). Classical conditioning is the learning of an association between a reflex behaviour and a previously unrelated environmental stimulus.
Box 2 Classical conditioning
In Figure 1 you can see how, to begin with, food (the unconditioned stimulus) elicits salivation (the unconditioned response). This is a ‘reflex’ response; it is unlearned and ‘built-in’ to the nervous system, like knee-jerking if the knee is tapped, or eye-blinking to a puff of air. The ringing of a bell at this point in time has no effect on salivation. Next the bell is regularly rung just prior to the food being presented. After a period of time the bell alone will elicit the salivation reflex in the absence of food. The bell has now become a conditioned stimulus and the salivation a conditioned response. This association can be weakened if the bell (conditioned stimulus) is regularly presented without the food (unconditioned stimulus). This process is called extinction. Extinction is the decline of a learned association between a stimulus and a behavioural response, as a result of the conditioned stimulus no longer being consistently paired with the presence of an unconditioned stimulus.
An example of how classical conditioning has been applied to understanding children's behaviour is found in the work of American psychologist John B. Watson (1878–1958). Watson gave the behaviourist school its name in his publication ‘Psychology as the behaviourist views it’ (1913). His belief in the power of the environment to influence development led him to make the following statement:
Give me a dozen healthy infants, well-formed, and my own specified world to bring them up in and I'll guarantee to take any one at random and train him to become any type of specialist I might select—doctor, lawyer, artist, merchant, chief, and yes, even beggar-man and thief, regardless of his talents, penchants, tendencies, abilities, vocations, and race of his ancestors.
(Watson, 1924, p. 104)
This reflects the behaviourist viewpoint that not only can behaviour be explained by examining the environment, but that by changing the environment the person's behaviour can be altered.
Watson's particular interest was the study of emotions. Together with Rayner he conducted an experiment into the conditioning of fear with an 11-month-old infant Albert B., more commonly known as ‘Little Albert’ (Watson, 1924).
When initially presented with a white rat, Albert showed no fear. Subsequently, the rat was shown to him four times. Each time a metal bar was ‘clanged’ behind Albert's head. On the fifth presentation the rat was shown but without the noisy ‘clang’. Although there was no noise, Albert still whimpered and moved away. He had learned to associate fear with the presence of rats through the process of classical conditioning. This response generalised to other previously neutral stimuli that were similar to the rat and which he previously had liked. He now also showed fear of furry toys, a fur coat and a Father Christmas mask. (Generalisation is when other neutral stimuli are sufficiently similar to a conditioned stimulus to elicit the conditioned response.) It should be noted that this study pre-dated ethical concerns about the potential of research to impact negatively on an individual's well-being.
The ethical implications of this type of study need careful consideration. Today any work carried out by psychologists must follow a professional ethical code, for example the British Psychological Society (BPS) ethical principles. It is unlikely that the ‘Little Albert’ experiment would be carried out nowadays.
Classical conditioning can only be used to re-train reflex behaviours (like crying when frightened or salivating when smelling food) and lead the individual to produce them in response to a new environmental stimulus. (Reflex is an instinctive, uncontrolled reaction to a given stimulus, such as salivating when presented with food.) However, what if a behaviourist needed a child to produce a response that was not a part of his or her repertoire of reflex behaviours? In this instance, operant conditioning would be used.