Psychology as behavioural science: how is this area affected by Pavlov, Watson and Skinner? - Chapter 9

Ivan Petrovich Pavlov (1849-1936) was interested in the congenital and reflexive saliva reactions in dogs, which he first called psychic secretions. It was about this saliva that arose automatically and involuntarily once there food was nearby. Pavlov saw that when dogs had become accustomed to the routine of the laboratory, they already started to drool as soon as they entered the research room came in. The dogs had associated the research room with food. These reactions were clearly learned and the result of experience and not of innate reflexes.

Pavlov saw himself as a physiologist and did not want to be associated with 'soft' psychology. After reading Sechenov's book, he became inspired enough to define his research into pure define physiological terminology. He called the psychic secretion conditioned reflexes and he called innate reflexes unconditioned reflexes. The relationship between the two could be examined in the laboratory and interpreted in physiological terms. Although Pavlov hated psychology, psychologists were interested showed for his work. One of those interested was Watson. He claimed the subject of psychology was the objective, observable behaviour, not the traditional mind and its subjective awareness. Inspired by the conditioned reflex of Pavlov, he became the founder of behaviourism.

What did Pavlov's life look like?

As a poor, but gifted student, Pavlov started to study physiology at the University of St. Petersburg. There he focused on the new mechanistic physiology and soon he was known as an exceptionally accurate researcher who even helped doctoral students to get their degree, even before he got his own degree in 1883. Not that he could get started right away: jobs in conducting research were rare. Only after he was forty did he become a professor the St. Petersburg military medical academy, where he set up his own laboratory to carry out his dream: an experimental study into the physiology of the digestion.

Pavlov was known for having two different sides, depending on his environment. In his personal life he was known as naïve, but in the laboratory he was the complete opposite. There he was strict: his animals had to be well fed and the laboratory always had to be well stocked and taken care of. The remarkable thing about his laboratory was its organization. Although he had difficulty organizing his personal life, he succeeded in keeping his laboratory in order very well. Experiments were systematically performed and repeated. New employees were never assigned to a new or independent project, but always had to test existing experiments again. If the new and the old results matched, the new employee could start a new project. Systematic work was something that Pavlov gotten a strain on early on, and that was what he learned to others: working systematically at the gathering of knowledge.

In his laboratory he started studying the effect of digestion. This was a research which was terribly difficult to perform, mainly because the bodies involved are very vulnerable. Organs did not function during an operation as they normally do. This did not allow their uses to easily be researched. Observing the organs therefore had only limited scientific value.

Inspired by a previously executed "natural experiment", Pavlov nonetheless knew to make a major contribution to the study of the function of digestion in operation. In the "natural experiment" carried out before, a French-Canadian trapper was injured by a shot wound in his stomach. His doctor Beaumont managed to get him back on his feet, but there remained a hole in his stomach, which soon functioned as a window. Beaumont could thus directly observe what happened in the stomach when the food was digested. In addition, he could be there insert instruments, to collect, measure and analyse substances. Pavlov decided the to replicate Beaumont's observations, but in a more selective and verifiable way. He did this by creating openings (or fistulas) in different parts of the digestion of the dog in a surgical way. Many had tried this before, but only Pavlov was successful in this, for two reasons: 1) he was an unusually successful surgeon who disliked had blood and thus tried to avoid it as much as possible and 2) he was one of the first who saw the value of antiseptic surgery, to prevent infections and the death of his animals as much as possible . One of the stomach reactions that Pavlov studied was saliva secretion. He discovered that one drop of dilute acid on the tongue of the dog produced a lot of saliva secretion. So he discovered the "psychic separation" of animals. Even before there is liquid on the tongue of the animal was dripped, it started to drool. Pavlov started this observation to study conditioned reflexes.

What are conditioned reflexes?

Pavlov's study consisted of systematically manipulating the four basic components of a conditioned reflex: the unconditioned stimulus (US), the unconditioned response (UR), the conditioned stimulus (CS) and the conditioned response (CS). A US and a UR together form the unconditioned reflex, a congenital and automatic response that does not result from conditioning or learning. Descartes previously had one unconditioned reflex described: the withdrawal of the foot (UR) when it came into contact with the heat of the fire (US). Pavlov also mentioned this earlier in his research, but then in regard to saliva. Pavlov noticed that a typical conditioned stimulus is neutral at first, so that it does not provoke specific reaction. However, after the US stimulus is offered several times at the same time with the CS (thus being coupled to it), this stimulus acquires the property to give the incentive for a specific reaction. For the dog, seeing the caretaker or the research room was the CS, which regularly followed by the US; food or acid in the mouth. The neutral stimulus soon provoked saliva with the dogs, without actually giving food. 

This became the stimulus response connection that Pavlov called the conditioned reflex. From another experiment where it time interval between a CS and US was varied, it appeared that the conditioning was the fastest as it was interval was short. Another experiment showed the higher-order conditioning. Here the highly conditioned saliva reflex was linked to another stimulus (such as a bell), after which it functioned as US, and then again be linked to another CS (such as light). This created a series of conditioned reflexes. Other experiments showed that conditioned reflexes could also be provoked by a stimulus that only resembles the original conditioned stimulus. This was what Pavlov called generalization. If in a workout a pitch is the conditioned stimulus, and then there is one slightly higher pitch was set up, then the conditioned reflex would still occur, but less than with the original stimulus. The greater the difference between the conditioned stimulus and the test stimulus, the weaker the generalized response. If a non - comparable stimulus was repeatedly presented, but not reinforced with the unconditioned stimulus, the response would decrease and even disappear. 

This was what Pavlov called differentiation. This is a form of learning in which the dog finds out that certain stimuli (that is perhaps first generalized), to be quite different. The dog learns to distinguish them. Pavlov also came with the experimental neuroses. After a reaction was generalized first, to then be differentiated again, then it later o will not be re-generalized again. The animal will then experience an experimental neurosis. This is a reaction that occurs when animals are confronted with an inevitable conflict between two strong, but incompatible conditioned responses. For example, if a dog cannot choose between, or do not drool, he can experience an experimental neurosis. Here the animal tries, for example frantically escape and remains unmanageable for a long time. Pavlov developed on the basis of this idea a theory about the functioning of the brain.

What was Pavlov's theory of the brain?

According to Pavlov, unconditioned reflexes are mediated by connections between the sensory and motor nerves in the spinal cord and lower brain regions. Conditioned reflexes are localized in the cortex. Pavlov suggested that different conditioned stimuli also activate different specific areas in the cortex. Similar stimuli are closer together. If conditioning took place, then two different processes in those brain locations are started: 1) excitation leads to the acquisition or generalization of conditioned reactions and 2) inhibition causes a response to be suppressed. Exciting processes in the cortical area occur as the presented stimulus is strengthened by an unconditioned stimulus. Inhibiting processes take place as the reinforcement did not take place or stays away. Pavlov also believed that excitation and inhibition can occur to spread. This has not been proven. If in generalization there was a similar alternative stimulus being shown, excitation took place in the cortical region, near the location of the original conditioned stimulus. That is why a reaction was triggered. This also happens with differentiation, but then there is inhibition.

What was Pavlov's influence?

The non-mentalist approach of Pavlov attracted the behaviourists in particular. But in unlike Pavlov, who called himself a physiologist, the behaviourists changed their definition of psychology so that the non-mentalist approach also fit into it. The behaviourists used similar techniques as Pavlov to determine their behavioural laws. For them, psychology was the science of behaviour, not the science of consciousness.

Who was Watson?

Watson (1878-1958) is seen as the father of American behaviourism. Because of pressure from his family, he almost became a pastor, but because the death of his mother and one small misstep at the university, he decided to continue studying nonetheless. He had trouble with the philosophical and introspective aspects of psychology but could totally find himself in studying and observing animals. He was attracted to the work of Jacques Loeb (1859-1924), a mechanistic biologist, and Henry H. Donaldson (1857-1938), a neurologist. Despite Watson’s troubles with traditional psychology, he nevertheless became pretty known in this area.

Because Watson could not find it in himself to like the traditional psychology, he decided to take this field and redefine it into behaviourism. He declared himself independent of the three ways traditional psychology: Behavioural psychology had to be completely objective. Subjective data or interpretations terms of conscious experiences did not fit there. In traditional psychology they namely only used objective observations to supplement introspective data. The purpose of psychology was not to describe and explain (something that traditional psychologists did) but predicting and controlling observable behaviour.

Traditional psychology distinguished between humans and animals. This distinction was denied by Watson. According to him, similarities were also important. Watson did experience problems with the behaviourist principles. Despite that he was against introspection as a psychological method, he knew no substitute method that better used to be. After reading about conditioned reflexes, in the work of Pavlov and Vladimir M. Bechterev (1857-1927), he also tried to condition people in an experimental way. In his book 'Behaviour', Watson wrote that images and thoughts could be studied with improved methods of introspection. The difference between Pavlov and Watson is that Pavlov was more interested in the brain than in the presenting behaviour. Watson was previously looking for a general principle, that was applicable on a lot of different species and behaviour. He saw the conditioned reflex as a model for a variety to reactions. He suggested that human emotions could be seen as glands muscle reflexes. Emotions could then be conditioned. If this was so true, then the Pavlovian conditioning found a behaviourist, non-introspective method to the most complex subjects and objects in psychology.

What are conditioned emotional reactions?

Watson limited himself to comparing animals in his first book. In his second book, he concentrated on human behaviour. Conditioned reflexes played a major role in his book. He started to wonder which emotional reactions are innate an unconditioned. To answer this question, he studied babies, who did not yet have time had to acquire conditioned reactions. He concluded that there are three types unconditioned emotional reactions, each produced by a small number of stimuli: Fear, provoked by 1) a sudden and unexpected sound, and 2) the loss of support (for example if you suddenly dropped a baby). Anger provoked by obstructing the movement of the baby. Love, provoked by manipulation or caressing erotic zones, tickling, soft rocking, knock or turn the baby so that it was on his stomach. According to Watson, all other reactions such as fear in the dark or love for the mother were conditioned. 

In 1919, when he wrote his book, he had no empirical evidence for this theory. It seemed plausible, but he had never seen how an emotional reaction was, in fact, conditioned. In 1920, he tried to solve this problem together with Rosalie Rayner (1899-1935) and until today the "Little Albert study" is one of the most famous and controversial studies in the psychological literature. It conditioned an 11 months old boy, Albert, to be afraid of a white rat. This was a stimulus that in the beginning was more of an interest rather than it aroused fear. As soon as Albert touched the rat with his left hand, there was someone who hit with a hammer on a piece of steel right behind Albert's head. The first time, he did not cry and only toppled right over in response. When he tried to touch the rat with his right hand this time, there was hit the hammer again. He fell again and started to cry this time. 

A week later, the rat shown again, and Albert kept his distance without crying. As soon as the rat was placed closer to Albert, the boy started to cry, and he tried to crawl away quickly. Five days later he still responded on the rat by crying and retiring. Watson and Rayner also tested the boy for generalization, by presenting any other hairy stimuli. With every stimulus they presented, Albert showed a weakened reaction, even when it took place in a different environment. In their article they described what they would have done to decondition Albert, but said deconditioning was something that never actually happened.

Watson moved to New York and went to work for an advertising company, J. Walter Thompson. He first gained practical experience and then helped with the planning of many innovative and successful advertising campaigns. He also continued to give psychology lectures and wrote in 1924 he the book Behaviourism. In his book "Behaviourism", Watson presented a case of "radical environment". This is a perspective in which the environmental factors are seen as more important in determining behaviour than heredity. In his earlier theory about emotions, Watson suggested all that different emotional reactions were the result of conditioning, based on three simple innate reflexes. Now he suggested that this also applied to all other aspects of the personality and behaviour of mankind. The innate factors are quickly adapted and developed through conditioning and experience. Features such as talent, temperament and character traits are not inherited, but acquired. Parental control was very important to him, considering they could form their children into anything under the right circumstances and conditions.

Watson felt that there was a thing such as unconscious thinking, but this was not the mysterious, metaphysical entity described by the psychoanalysts. He started defining of the conscious thought as being a collection of vocal or sub-vocal, verbal reactions. With other words: conscious thinkers literally talk to themselves. Every verbal response serves as stimulus to call a new response. These newly provoked reactions do not have to be verbal but can also be visceral or kinesthetic and can involve emotional reactions. The non-verbal reactions serve as links into thinking and thus evoke their own verbal or non-verbal verbal responses. They thus function as important, emotionally charged parts of it thinking process, but because they are non-verbal, they are not perceived as conscious.

What is systematic desensitization?

Now that Watson knew that emotional reactions could be created, he also wanted to know if he could reduce them or even make then disappear. Together with Mary Cover Jones (1896-1987) he tried to explain this. Jones tested the idea with a child (Peter), who showed fear of rabbits. Every time when the rabbit was shown, she also ensured that a pleasant stimulus (candy) was present. The rabbit was slowly pushed towards Peter in the presence of the candy, until he could finally play with the animal without showing fear. Jones called this procedure direct conditioning. Other children who were not afraid of rabbits were also involved with the procedure. In the end, direct conditioning and social imitation proved to be very effective. This was the first successful demonstration of systematic desensitization.

Watson suggested that parents should have control over their children's environment so that the most suitable conditioned reflexes could be developed. In his book "Psychological Care of Infant and Child", he described how parents could prevent the emergence of inappropriate conditioned emotional reactions. The home environment had to be safe and secure and inappropriate fear inducing sounds and actions had to be avoided as much as possible. Clothes that babies wore should not be too tight, so that the child could move about freely, and anger was avoided. Watson thought the most important thing was that children should never be stimulated to develop love reactions, when they were expected to develop independent behaviour. Despite the "principles" he described in his book, he acknowledged that there was no ideal way to educate children and that what behaviour is desired varies from person to person.

What did Watson leave behind?

Despite the fact that Pavlovian conditioning is seen as an important form of learning, it has been shown that it is inadequate for the active way in which organisms learn to manipulate and control their environment. Language and thinking are more than a succession of verbal, visceral and kinesthetic reflexes. Also, due to the emphasis on the environment, the effects of heredity should not be forgotten. Yet, the ideas of Watson were not complete turned down. Some still define science as the study of behaviour and find that their data must be observable and objective. Predicting and controlling behaviour is still one of the ongoing goals of psychologists and the study of learning and conditioning is still one important area in psychology. Watson has had a lot of influence on neo-behaviourism.

Psychologists such as Edward Chace Tolman (1886-1959) and Clark Hull (1884-1952) also followed the example of Watson. However, they tried to, under the influence of a philosophy, also called known as logical positivism, derive and test theories about behaviour. Logical positivism attempted to translate non-observable constructs into observable constructs. Tolman is best known for his experiment with mazes, where the concept is to demonstrate latent learning. 

In this experiment, Tolman placed a group of rats in the maze and left them to freely walk around there. A second group of rats could also roam freely and if they were successful in navigating through the maze, they were rewarded with food. A third group of rats was also allowed to roam free, but initially without reward. Only on the eleventh day a reward was introduced for this group. If latent learning had taken place, then the rats in the third group would have to show fewer navigation errors as soon as the reward was introduced. This was indeed what happened. During the first ten days the rats from the second group made errors similar to the rats from the third group. The mistakes of the rats from the second group had decreased during the ten days. Once the reward was introduced in the third condition, the rats from the third group outperformed the rats from the second group, by quickly running through the maze.

Tolman used these experiments to explain his theory about goal behaviourism support. This theory means that all behaviour is goal-oriented. The position of Hull (which sometimes is called mechanistic behaviourism) is about determining complex mathematical laws where learning was put down in terms of specifiable relations between operations defined variables such as habit, strength and stimulus intensity. Someone else through who is Watson became inspired, but who took a different position than neo-behaviourism, was B.F. Skinner (1904-1990).

Who was Skinner?

Burrhus Frederic Skinner (1904-1990) was born in Pennsylvania. He had musical and literary talent. At the age of 10, he wrote his first literary work, a poem. In 1922, he went to Hamilton College in Clinton. Here he followed biology and philosophy lessons. He graduated in English and wrote for different magazines. After graduating, he moved in with his parents and tried to become a professional writer. He experienced a depression and writer's block there. At one point, he became interested in the books of Watson and Pavlov, and appreciated their points. He became a behavioural psychologist.

What is operant conditioning?

What for Pavlov was the saliva reflex device became for Skinner the Skinner box. The Skinner box made it possible for him to produce and to study a different kind of learned behaviour, which he called operant conditioning. Four non-formalized principles (used and discovered by Skinner) of scientific practice led to success: If you come across something that is interesting, drop everything and study it. Some research methods are easier than other research methods. Devices can sometimes fail. Some people are just lucky.

Learning in daily life was more than just the passive acquisition of reflex reactions according to Skinner, and that is the point where he disagreed with Watson and Pavlov. Organisms also learn to actively manipulate and control their environment. This was already demonstrated by Thorndike with his chickens. Skinner called this form of active learning operant conditioning, in which organisms influence their environment and experience the consequences.

The Skinner box was a cage for a white rat with a lever on the wall, plus a tray. The tray was connected to the lever. When the lever was pressed, it opened up a gap so food could fall into the tray. The lever was also connected to a pen and a paper outside the box. The number of times the lever was pressed was displayed in a curve on paper. The cumulative curve is thus the total number of times the lever was pressed. Skinner also varied the specific conditions in which the reactions of the rat were or were not enhanced with food ("Contingencies of reinforcement"). The extinction curve Skinner discovered by accident, when the food dispenser stalled (think back to Skinner's third and fourth principle). First the rat quickly pressed the lever, partly because he no longer stopped to eat in between and partly because he was frustrated because he got nothing anymore. After a few minutes, the speed with which the rat was pushing the lever went down until the rat finally stopped pushing and the curve also disappeared.

There are four excitation schemes. The rat is given in a fixed interval ratification scheme for example every three minutes an endorsement (a block of cheese). In a fixed ratio ratification schedule, the rat receives only an endorsement after a certain number of reactions, for example, after having pressed the lever four times. At the variable interval and the variable ratio ratification scheme, the time or number of responses varied. This arises a kind of constant hope that the next response will be rewarded (the same principle as with gambling). In this condition, the rats continued to react much longer after no reward more was given.

Operant conditioning is a different way of learning than the Pavlovian conditioned reflex. Yet the discovery was just as important. Skinner called the Pavlovian learning method "Respondent conditioning". The two learning methods differ from each other in many areas: Respondent conditioning creates new connections between stimuli and reactions while with Operant conditioning, you can allow existing reactions to increase or decrease. With respondent conditioning the reaction is triggered by a conditioned stimulus, while with Operant conditioning the behaviour must first be shown by the participant before conditioning can take place. With respondent conditioning, the conditioned and unconditioned stimuli are precisely defined, while in operant conditioning not it can be said with certainty which stimuli provokes the reaction. The strength of the respondent conditioning is measured in terms of reaction strength or latency, while it is at operant conditioning in terms of reaction speed is measured. With the operant conditioning Skinner has developed a controlled and appropriate behaviouristic method.

What is programmed instruction?

Complex behaviours resemble a chain. Skinner developed a complex method to provoke simple reactions in animals. He used an empowerer and started with respondent conditioning to link the sound of ticks to a toy clicker with help of a strong primary reinforcer such as food. After a while, the sound of the ticking became the secondary reinforcer. He used the secondary reinforcer to create a further series of more complex system to form reactions. He also developed a programmed instruction. This is an educational technique involving complicated subjects such as mathematics that are broken up in small, easy-going components. In the beginning one works with easy questions, but the difficulty level slowly increases. These programmed instructions are still being processed applied and are very valuable.

What are the philosophical implications of operant conditioning?

Skinner felt that when the negative reinforcers simultaneously were considered with the positive reinforcers, all behaviours would be determined by unforeseen reinforcers (or chance). The concept of free will therefore would not exist. Skinner suggested that when we believe that we act out of our free will, we are actually free of the negative reinforcers and that we are mainly free to pursue the positive reinforcers. This he described in his book "Walden Two". Herein, he describes an ideal society in which positive reinforcement is used for social controle. Children are only taught to look up the positive amplifiers so that they can eventually show social and civilized behaviour. Walden Two was very controversial and the 'ideal' society was depicted as totalitarian.

According to Skinner, we only acquire knowledge through the experience of accidental reinforcers. The knowledge we have gained can only be shown by our verbal behaviour. Noam Chomsky criticized this idea of ​​Skinner. His argument was that the behaviourist theories were too inaccurate to explain the complex multiple levels, in which grammatical structure were represented and developed. Chomsky was also of the opinion that only human babies can acquire the ability of language, because only they had an innate knowledge about the fundamental structure of language.

In the book that Skinner published in 1971, he discussed the assumption of autonomous man, on which many Western societies were based. Skinner did not agree with this assumption and was of the opinion that this could have harmful consequences. According to the assumption, we compliment people more often for good deeds they do voluntarily, than for deeds they do must do. According to Skinner, we do not know the circumstances and the situation in the first case, or who are responsible for producing the behaviour. In the second case, we do know. He found that when people were complimented for an unexplained good behaviour, then they also had to be punished for their voluntarily produced bad behaviour. The assuming that people are free, therefore demands punishment and according to Skinner, this assumption is a threat that is constantly used to exercise control over behaviour. In his further experiments, he suggested that positive reinforcement in producing lasting conditioned effects was more effective than negative reinforcement (punishment). Therefore we have to let go of the belief about freedom and accept control, in order to create a good environment to be able to create where socially desirable behaviour can be formed. What was not clear in his theory is who must create that environment.

What is the influence of Skinner?

The Skinner approach ("behavioural analysis") is still being used. Skinner's ideas have been used to find a treatment for autism, for example. Being in education behavioural principles used to help children with ADHD and learning disabilities. Also in the field the Skinnerian training techniques are still used for animal training.

 

ExamTips

  • When you have difficulty understandin the difference between classic and operant conditioning, try to draw up a scheme of it in terms of reaction and stimulusses. It will help you differentiate between them.
  • Why was Pavlov so important for the advancement of our modern psychology?
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