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In Psychology, the Behaviourist School operated on the idea that the vast majority, if not all, of our behaviour is learned from our external environment. The Behaviourist school teaches us that learning is not a result of our biology. It is learned through imitation, trial and error and shaping. Behaviourism blossomed in the early 20th century and it was particularly popular in the United States of America. The Learning Theory is that the majority of learning happens either from the strengthening or weakening of associations. Early investigators, including Pavlov, conducted experiments using simple creatures such as dogs, pigeons and rats in simple learning situations, in the hope of discovering the basic laws of learning. Pavlov noticed that his dogs began salivating, even when there was no food actually present. He realised that some other stimulus was setting about this response. He set up experiments to show that the dogs could salivate to a chosen stimulus that he would teach them to associate with the food. Watson and Ray nor read about Pavlov’s work and they proceeded to develop their own ideas about association. They are most well known for the Little Albert study. Edward Thorndike created the Cat in a Puzzle Box experiment to demonstrate how we learn by trial and error. His work was then taken up by Skinner who developed a learning technique in rats called shaping.
Behaviourists are very critical of the methods used in other areas of Psychology. Behaviourists want to use methods that are entirely scientific in nature and they are not concerned with anything that cannot be observed and measured. A key feature of Behaviourism is that all behaviour is caused in some way and the external
environment is the biggest influence on our behaviour. We learn by association and as such, we associate stimuli from the environment with our responses. Behaviourists say that this cause and effect relationship can allow us to predict and control the behaviour of animals and our fellow man. Behaviourists are not concerned with internal factors, such as the mind, or anything else that cannot be observed and measured. Behaviourism looks at the connection between stimuli and response, suggesting that this is how learning takes place.
Ivan Petrovich Pavlov was a Russian psychologist. In the course of unrelated research on the digestive system, Pavlov noticed that his dogs salivated when there was no food present. He realised that the salivary reflex could be set off by other stimuli that at first, were completely neutral. It was Pavlov who proposed a distinction between the conditioned reflex and the unconditioned reflex. He conducted experiments to try to elicit the same response using other unrelated stimuli.
(US) Unconditioned Stimuli. Stimuli that we are naturally programmed to respond to e.g. Food, loud noises.
(UR) Unconditioned Response. A response that is innate and free from any learning e.g. Salivation, blinking, and goose bumps.
(CS) Conditioned Stimuli. Learned Stimuli.
(CR) Conditioned Response. Responses acquired through experience and learning.
Pavlov used a technique called Classical Conditioning. Classical Conditioning is achieved through reinforced trials. The conditioned response is achieved through repetition. The connection between the (US) unconditioned stimulus and the (CS) conditioned stimulus must be reinforced several times before the (CS) conditioned stimulus is able to elicit the (CR) conditioned response by itself.
Pavlov repeatedly presented the dog with a large black square (CS) along with the food (UR). This elicited salivation (UR). Repeatedly presenting the (CS) and the (UR) is known as Reinforced trials. Pavlov found that after enough reinforced trails of this kind, he was able to present the black square on its own to the dog and the dog would still salivate. Salivation becomes the conditioned response (CR). From this we are able to conclude that Pavlov was able to prove that learning could occur as a result of associations.
Pavlov was also able to show that the conditioned response could be undone. He illustrated that the (CR) would eventually disappear if the conditioned stimulus was repeatedly presented on its own. The term for this is Extinction. Extinction is achieved through unreinforced trials, as the (CS) is not reinforced by the (US). Without this reinforcement, the (CR) will disappear. If, on a separate occasion, the reinforced trials were repeated, the (CR) would appear again much quicker than on the first round of trials. This is called Reconditioning and it is typically faster than Classical Conditioning because the memory of the (CS) is not gone, simply weakened. This is an example learning through the weakening of associations. The memory provides the organism with a head start in the reconditioning trials.
Animals must be able to respond to stimuli that is not identical to the original (CS). It is not surprising that animals show a pattern of stimulus Generalisation. The ability to generalise has allowed animals to respond to a variety of stimuli, provided it is sufficiently similar to the original (CS). The less familiar the stimuli to the original (CS), the weaker the response will be. This is called a Generalisation Gradient.
Generalisation is undoubtedly very useful but it can also be taken too far. Therefore, a level of Discrimination is required. Discrimination can be achieved through unreinforced trials until the animal learns to discriminate perfectly.
Watson and Raynor read about Pavlov’s work with dogs and proceeded to conduct their own experiments. They are most famous for the Little Albert study. When Little Albert was a child, he was presented with a fluffy, stuffed, white rabbit. Whenever the child reached for the rabbit, Watson and Raynor would make a very loud, sudden noise. In response, the child would be frightened and would cry. This was repeated several times. Eventually, the child would cry whenever he was presented with the rabbit, regardless of whether there was a noise to accompany it or not.
This is another example of Classical Conditioning. This experiment was significant because it shows that humans could learn to associate two stimuli together. The (CS) was the fluffy rabbit and the (US) was the noise. The (CR) was the child’s fear and crying. When the (CS) and the (US) are presented together often enough, the child learned to associate the rabbit with frightening noise and became afraid of it. What was not expected of this experiment was that the child learned to generalise his fear to white, fluffy objects that resembled the white rabbit. Like all other forms of this conditioning, it could have been undone but at this point, Little Albert’s mother became uncomfortable with the situation and she withdrew her consent.
Skinner went on to develop the theory of Operant Conditioning. This is an example of Instrumental Learning. The key feature of this theory is that the subject has to behave in a certain way first. Reinforcement or reward depends on the subject exhibiting the right behaviour. If the consequence is pleasant, the subject learns to repeat the behaviour. Skinner refers to anything that will cause the behaviour to be repeated as a Reinforcer.
Skinner used rats in his experiments. He would place the rats in a box with a lever and watch closely. Whenever the rat pressed the lever, a pellet of food would be delivered. After this, the rat is attracted to that area of the box and will return over and over again to repeat the behaviour. In this case, the food is the reinforcer. The rat learns to associate the lever with the food.
There are two types of reinforcement in Operant Conditioning. Positive and Negative. Positive Reinforcement is where the consequence of a particular action is pleasant. The subject will be encouraged to repeat the behaviour for the reward e.g. food, toys. Negative Reinforcement is when the animal avoids an unpleasant consequence of not displaying the desired behaviour, for example, the rat jumps onto a platform in order to avoid an electric shock.
Skinner also experimented to see if the behaviour would be repeated if the subject did not receive reinforcement every time the behaviour was displayed. He devised Schedules of Reinforcement. He observed that in all cases, the subjects continued to give the correct response, even when they were only reinforced for doing so every few times.
Thorndyke illustrates the Law of Effect with his Cat in a Puzzle Box experiment. He placed a cat into a large puzzle box with a lever at the end. When pressed, the lever would open the box and allow access to the food outside. At first the cat struggled for a long time and then pressed the lever purely through accident. The second attempt took a little less time, as did the time after this. This shows Response Latency. The cat took many attempts to learn about the lever. The results are not what would be expected if the cat showed any understanding. Sudden insight would result in much quicker training.
Operant Conditioning can be used in a number of ways. One of the best known ways is Shaping. This involves training the subject do perform more complicated learning tasks than would normally be expected of them through the reward of each small step closer to the desired behaviour. Rats can be taught to press levers that are out of their eye line and out of their normal reach through shaping. The rat would first be rewarded for facing the correct way. Then it would be rewarded for being in the correct area in the box. Then for looking up. Then for pulling itself up and finally, for pressing the lever. After this, the rat will reach up and pull the lever without having to be rewarded at each step, whereas at the beginning, it would not occur to the rat to even look up.
Behaviourism is very scientific and reliable, but it can be criticised to a certain degree. Not all behaviour that we exhibit is conditioned, therefore Behaviourism cannot explain all of our behaviour. It does not take into account internal factors, such as the mind and our cognitive processes. Also, the research that forms the foundations of Behaviourism was done predominantly on animals in laboratory settings so how can we be sure that this research will apply to us as well?
Despite the criticisms, Behaviourism has contributed much to the field of Psychology. In their attempts to explain behaviour scientifically, they have made Psychologists much more credible and they allow people to explain their behaviour in a scientific way. There are many positive uses for conditioning that help and enrich the lives of people such as Aversion Therapy, which is the treatment of phobias. Behaviourists are always objective and they use scientific methods to support valuable and relevant conclusions.
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