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Classical Conditioning
UNIT 1 CLASSICAL CONDITIONING BY By Pavlov
PAVLOV
Structure
1.0 Introduction
1.1 Objectives
1.2 Concept of Classical Conditioning
1.3 Pavlov’s Experiment on Classical Conditioning
1.3.1 The Experiment 1.3.2 Interpretation of the Results of the Experiment 1.3.3 Principles of Classical Conditioning
1.4 Implications of Pavlov’s Classical Conditioning in Understanding Personality
1.4.1 Conditioned Emotional Responses – the Case of Little Albert 1.4.2 Classical Conditioning of Social Attitudes 1.4.3 Psychopathological Conditions Explained by Classical Conditioning
1.5 Applications of Classical Conditioning in Psychotherapy
1.6 Critical Evaluation of Classical Conditioning
1.7 Let Us Sum Up
1.8 Glossary
1.9 Unit End Questions
1.10 Suggested Readings
1.11 Answers to Self Assessment Questions
1.0 INTRODUCTION
Does your baby daughter start crying whenever she sees a man with big moustache? Does your brother fall helplessly in love with every lady who uses a particular perfume?
The fear of your child, the blind attraction of your brother, may have at their bases, the principles of classical conditioning. Both of them may have been behaving precisely like ‘Pavlov’s dog’.
How did your daughter develop the fear? You may recall the incident when your uncle with a pair of long moustache visited your house. Holding your daughter in his big burly arms, he had bellowed ‘Hey there - my sweetie’. Even you jumped up at the sudden sound. Your little girl was terrified and cried out in fear. Your uncle was a bit embarrassed and tried to soothe the baby. ‘Now, NO - NO… No more crying ..’ he roared. The baby now got so scared that you had to intervene and take her from the boisterous grandfather’s arms. Since then she had been scared of any man who happens to have a bunch of bushy hair below his nose, causing your anxiety and your uncle’s mortification.
What had happened? The sudden loud sound caused a startle response in the baby generating the emotion of fear. Every time the frightening sound emerged, the baby
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saw a pair of dancing bushy moustaches – the most prominent feature on your uncle’s face. So this innocent growth of hair, the sign of pride for your uncle, became the sign of danger to your daughter. She anticipated the frightening roar whenever she encountered any man with moustache and cried even before the sound came. The fact that your daughter has thus acquired this new and uncomfortable association of the moustache and the sound is an instance of Classical conditioning. But you can erase this learning, or put new learning in her also. In this Unit, you will know about Classical conditioning. Classical conditioning is one basic model of learning which was a landmark in the history of understanding behaviour. The man behind it was a Russian physiologist named Ivan Petrovich Pavlov. In this Unit, you will learn about Pavlov’s basic experiment, the concepts emerging thereof, and the application of classical conditioning in personality theory and psychopathology.
1.1 OBJECTIVES
After going through this unit, you should be able to: l Define classical conditioning; l Describe Pavlov’s experiment in classical conditioning; l Differentiate among unconditioned stimulus, unconditioned response, conditioned stimulus and conditioned response; l Draw a schematic diagram of classical conditioning experiment with its essential elements; l Explain the implications of Pavlov’s classical conditioning in understanding personality; and l Discuss the applications of classical conditioning in psychotherapeutic settings.
1.2 CONCEPT OF CLASSICAL CONDITIONING
Classical conditioning is a learning paradigm from behavioural point of view. Consider any stimulus (S1) capable of eliciting a natural response (R1). Imagine any other neutral stimulus (S2) that does not elicit this particular response. Suppose within the experimental situation, these two stimuli (S1 and S2) are consistently presented together. After a few exposures of S1 and S2 together, the natural response to the first stimulus (R1) would occur in the presence of the second stimulus (S2) also, even if the first stimulus (S1) is absent. Thus after conditioning, the second stimulus, originally incapable of eliciting the specific response, becomes capable of doing the same. Consider the example of the boisterous uncle. The loud voice was the natural stimulus (S1) that elicited the natural fear response (R1) in the child. The moustache was, originally, a neutral stimulus (S2) incapable of eliciting fear. But, as it always accompanied the big sound, it gradually became capable of eliciting the fear, even when the sound was absent. The term classical conditioning is define as learning by association, whereby a neutral stimulus, by virtue of its occurrence in close time and space with a natural stimulus that gives rise to a natural response, becomes capable of eliciting that natural response, even in absence of the natural stimulus. Classical conditioning is applicable only for reflexive and spontaneous responses, and not for voluntary responses.
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the association was established, the dog elicited the saliva in response to the bell. Thus, it was a new learning for the dog. Pavlov identified four essential elements of the learning processes. They are: i) Unconditioned stimulus (UCS): The natural stimulus that elicits a natural response. In Pavlov’s experiment, the meat powder was the UCS. ii) Unconditioned response (UCR): The natural response elicited to the natural stimulus. In Pavlov’s experiment, the salivation was the UCR. iii) Conditioned stimulus (CS): The neutral stimulus that does not naturally elicit the target response, but may do so after being associated with the UCS for a number of times. In Pavlov’s experiment, the light or the sound of the bell was the CS. iv) Conditioned response (CR): The target response similar to the UCR that originally occurred to the UCS only, but after conditioning occurred to CS, even in absence of the UCS. In Pavlov’s experiment, the salivation that occurred in response to the light or bell was the CR. You must remember here that the UCR and the CR are similar but not the same. Pavlov noticed that the amount of salivation was less in response to the light / bell in comparison to the original salivation in response to meat powder.
Box 1 Before conditioning: UCS (food) ————UCR (salivation) NS (bell) ————————No salivation During conditioning CS (bell) ———— UCS (food) ————UCR (salivation) After conditioning CS (bell) ————CR (salivation)
(UCS -unconditioned stimulus, UCR- unconditioned response, NS- neutral stimulus, CS- conditioned stimulus, CR -conditioned response) You must remember that classical conditioning is not limited to salivation and similar other anticipatory approach responses only. One may condition anticipatory withdrawal responses as well. Pavlov examined this phenomenon by delivering an electric shock to the paw of the dog. On each learning trial, the bell rang and the shock was delivered immediately after. The reflexive withdrawal of the paw, a natural response to the shock, now started to take place after the sound of the bell and before delivery of the actual shock.
Box 2 Before conditioning : An electric shock given to the dog ——— Dog withdrawing its paw Ring the bell ————No withdrawal of the paw by dog During conditioning : Ring the bell ——— Give electric shock to the paw of the dog ———dog withdraws its paw After conditioning : Ring the bell ——————————— Dog withdraws its paw
Classical Conditioning By Pavlov Pavlov used the term ‘acquisition’ to denote the new learning. In classical conditioning the acquisition occurs due to temporal contiguity of the stimuli , or association in time. In the following section we would see how varying this association may influence the learnt behaviour.
Self Assessment Questions 1
- Who was Ivan Petrovich Pavlov? What is he famous for? ................................................................................................................ ................................................................................................................ ................................................................................................................
- What is classical conditioning? ................................................................................................................ ................................................................................................................ ................................................................................................................
- Tick the correct answer for questions a, b and c : a) In Pavlov’s experiment, the sound of the bell was the (i) UCS (ii) CS (iii) UCR (iv) CR b) In Pavlov’s experiment, food was (i) UCS (ii) CS (iii) UCR (iv) CR c) In Pavlov’s experiment salivation is the index of i) both UCS and UCR and they are identical. ii) both UCS and CR and they are identical. iii) both UCS and CS but they are not identical. iv) both UCR and CR but they are not identical.
1.3.3 Principles of Classical Conditioning
Now you know that the food was given to the dog just after the light / sound of the bell and conditioning resulted. Have you thought what would happen if the sound of the bell came after the food? Have you considered whether the bell would continue to elicit salivation if meat powder was not given to the dog for a number of times?
After formulation of basic principles of classical conditioning, Pavlov engaged himself in exploring and illustrating some of principles of classical conditioning. In the following sections you would learn about some such principles.
i) Reinforcement: You know that you can elicit a conditioned response by the pairing of CS and UCS. Since UCS (meat powder) comes later than CS (bell), the presentation of CS alone elicits salivation. But you need to give the dog the UCS consistently after the bell. So here meat powder serves as the reinforcer, as it strengthens the bond between the CS and the UCR (salivation in this case). Reinforcement is a very important concept in conditioning. Reinforcement refers to the presentation or removal of a stimulus to maintain or increase the probability of a target response. Reinforcement may be primary or secondary and positive or negative. Primary reinforcers are those that satisfy a basic need. The food in
Classical Conditioning By Pavlov will be slightly less than the conditioned response. If on another test trial you expose the dog to even another sound which is a bit more dissimilar to the original CS, the amount of salivation will be even less. Thus for successively less similar stimuli, decreasing amount of salivation will be obtained. You will get, as a result, a gradient of conditioned response.
v) Discrimination: This is the opposite of generalisation. You have learnt that generalisation occurs to stimuli similar to the CS. But if stimuli similar to the CS and eliciting the CR are presented repeatedly without ever being associated with the UCS, those stimuli will cease to elicit the CR, thus enabling discrimination between similar stimuli. Suppose the original CS is the sound of a bell that we call B. The dog learns to salivate to B, and also salivates to B1 and B2 through generalisation. However, if B1 is systematically reinforced and B2 is not reinforced, then the dog will respond differentially to B1 and B2. It will salivate to B1 and not to B2.
vi) Counter conditioning: Once conditioned, ever conditioned? Of course not. As you can extinct an acquired learning, you can also counter condition it by associating the CS with UCS of different nature. For example, you can first condition a dog to withdraw its paw at the sound of a bell, as the bell is systematically followed by a shock. Then you can countercondition it by systematically pairing the same sound to food. Now the dog may be conditioned to salivate to the sound of the bell.
Self Assessment Questions 2
- Write True (T) or False (F) beside each statement: a) Repeated exposure of the CS without reinforcement will lead to extinction ( ) b) The animal, after conditioning will respond with the conditioned response to the specific stimulus only and not to other similar stimuli ( ) c) Once conditioning has taken place, it cannot be changed ( )
- Tick the correct answer a) A cat has been subjected to a red light immediately before an electric shock. As a result it has learnt to withdraw its paw when it sees the red light. Subsequently it is being exposed to a red light immediately before getting food. This is an example of (i) reinforcement (ii) counter conditioning (iii) discrimination (iv) extinction. b) A rabbit has been exposed to a red light before being delivered a pellet of cabbage leaf. As a result it salivates to red light alone. Subsequently the experimenter wants to see if it can generalise its learning. Which of the following stimuli would be appropriate to demonstrate generalisation? (i) cauliflower leaf (ii) blue light (iii) pieces of carrot (iv) orange light
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1.4 IMPLICATIONS OF PAVLOV’S CLASSICAL
CONDITIONING IN UNDERSTANDING
PERSONALITY
So far we had been dealing with dogs. But we started the chapter with your little daughter. How do we pass on from the dog’s saliva to the baby’s fear? How far this fear conditioned in your daughter may make her an anxious woman throughout her life? In this section, you will learn about the application of classical conditioning principles to complex human behaviour and personality characteristics. Pavlov’s lead was followed by a number of behaviourists. They conducted experiments with conditioning and deconditioning of various emotional and social behaviours. Among the earlier works in this direction, the most famous is the case of Little Albert reported by John Broadus Watson (1878 - 1958).
1.4.1 Conditioned Emotional Responses - the Case of Little
Albert
A classic experiment conducted by John B. Watson and Rosalie Rayner in 1920. Watson was an ardent behaviourist and a critic of complex psychoanalytical explanation of emotion (Watson, 1913, 1920). They worked with an 11 month old boy called Albert. Watson and Rayner were able to instil fear of rats in the boy. Initially, Albert was not afraid of rats and used to play with rats fondly. Watson and Rayner exposed the boy to white rats and simultaneously made a very loud sound by the bang of a hammer on a suspended steel rod. The loud sound produced a startle response in the boy. After a series of such exposures, Albert showed signs of fear of rats. Gradually his fear was generalised to many other furry objects like rabbit, dog and also cotton balls. Watson and Rayner claimed that this experiment proved that irrational fear of apparently harmless things is not due to deep emotional complexes but owing to simple temporal association of fear generating objects. Although you might think that the results are straight forward enough, actually there a few gaps. Later investigations suggested that Albert’s fear was perhaps neither as strong as claimed, nor as much generalised. There was a gross ethical violation involved as well, at least by today’s standard. Albert’s fear was never de conditioned. ( Source : You can see the experiment of Albert by Watson and Rayner in the internet by clicking ) Watson and Reyner succeeded to show that at least some degree of conditioning of emotional reactions is possible. It has further been supported by the clinical cases where de conditioning of irrational fear has been made. In 1924, Mary Cover Jones reported de conditioning of a 3 year old boy’s fear of rabbit. This boy, called Peter was exposed to other children who were not afraid of rabbits. The presence of rabbit was also associated in time with pleasurable activities and playful words. Gradually through a repeated association of rabbit with pleasant things, Peter could outgrow his fear. This experiment also paves the way for using classical conditioning principles in therapeutic setting. In the following section, we will learn about the classical conditioning of attitudes.
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encounters with the teacher. The tension associated in those instances caused severe gastric contraction in her for a few times. Then it got conditioned to the teacher’s presence, and each time she had to encounter this teacher, she felt the gastric contraction, even though the events for tension were absent. You must remember that while the explanation by classical conditioning may be tenable in some instances of psychopathology, in most cases, the causes are much more complex. However, attempt to treat such pathologies with deconditioning of faulty acquisition and counter conditioning in a desirable manner has been successful at least partially in treatment of such disorders. In the next section we shall get acquainted with such principles of psychotherapeutic intervention based on classical conditioning.
1.5 APPLICATION OF CLASSICAL
CONDITIONING IN PSYCHOTHERAPY
Let us discuss the therapeutic techniques that utilise the principles of classical conditioning. The most well known application is in case of systematic desensitisation. Consider a case of phobia. In phobia, as in case of Little Albert, the person is irrationally afraid of certain neutral things. You may assume that the fear is the result of some kind of classical conditioning. Therefore the principles of extinction and counter conditioning may be used to free the person from the irrational fear. The technique of systematic desensitisation was introduced by a psychologist named Joseph Wolpe (1915-1997). In this technique, the subject is exposed to the object of fear in a graded manner. Suppose, as in Albert’s case, the rat is the object of irrational fear. As therapist you must design a step by step exposure to rat. Initially you may show him a picture of the rat from a distance and ensure he is fully relaxed. When the picture is acceptable to the child and he is relaxed enough, a plastic model of rat may be shown to him. Gradually you may try a live rat, but from a distance so that the child is not traumatized. When the child accepts the rat at a distance, you may gradually think of bringing it closer to him. This is utilisation of the principle of extinction. But your work will be facilitated if you also associate something pleasant with the rat. For example, every time the picture of the rat is shown to the child, you may offer him a candy. The child will learn to associate rat with something pleasant. Thus along with extinction, you may also utilise the principle of counter conditioning.
Self Assessment Questions 3
- Tick the correct answer a) The case of Little Albert demonstrates that i) social attitudes can be conditioned, ii) emotions can be conditioned, iii) fear can be de conditioned, iv) classical conditioning can be used in therapy. b) The psychologist who developed the notion of systematic desensitization was: i) Joseph Wolpe, ii) Gregory Razran, iii) Rosalie Rayner, iv) Ivan Pavlov. c) Social attitudes can be brought in one’s favour by associating the object of attitude with (i) unpleasant stimuli (ii) systematic graded exposure (iii) pleasant stimuli (iv) persuasion.
1 5
Classical Conditioning
- Give the suitable answers to the following: By Pavlov i) What is Luncheon technique? ........................................................................................................ ........................................................................................................ ........................................................................................................ ........................................................................................................ ii) What is aversion therapy? ........................................................................................................ ........................................................................................................ ........................................................................................................ ........................................................................................................
1.6 CRITICAL EVALUATION OF CLASSICAL
CONDITIONING
Classical conditioning has been criticized for providing a mechanical view of human behaviour. It ignores the role of cognitive factors in learning. There are ample evidences that cognitive factors like motivation, expectation and attitudes help or hinder learning. Particularly in the case of human beings, cognitive factors are of immense importance. In fact, it has been observed that if a stimulus is well exposed to the animal or human before conditioning, then it cannot be used easily as a conditioned stimulus (CS). That is already formed ‘attitudes’ hinder its use as a CS. Thus classical conditioning is not as simple and mechanistic as it seems. Consider the case of the child suffering from oppositional defiance disorder. The aggressive motive of the child may far surpass the impact of simple reinforcements and the disruptive behaviour continues till the cognitive and affective parts are taken care of. Similarly, consider the case of physically challenged persons like Helen Keller who, by sheer motivation and grit succeeded to overcome the handicaps. Perhaps, the principles of classical conditioning are not adequate for explaining such cases.
A second criticism has come from the strict biological standpoint. You cannot condition any species beyond its biological limitation. Furthermore the biological instinct to survive interacts with the conditioning paradigm. It is easy to condition a person to hate and avoid specific food, but conditioning the same person to hate and avoid flowers would be much more difficult. One is biologically more predisposed to be afraid of poisoned food for basic survival reasons than of poisoned flowers. The critics assert that classical conditioning in such cases is just working on the biological predispositions.
A third critique of application of classical conditioning has come from ethical perspective. There have been unconfirmed reports of classical conditioning being used unethically on war prisoners of different countries, and unethical use of classical conditioning in advertisements.
All of these criticisms point out correctly to the limitation of classical conditioning principles. But that hardly makes it redundant. In fact, in recent years, the interest in classical conditioning principles has been renewed, as it has been observed that our immunity system may be classically conditioned (Ader and Cohen, 2001; Niemi,
- and therefore, these principles seem to have impact on our health.
Classical Conditioning By Pavlov Extinction : In the classical conditioning paradigm, when a conditioned stimulus ceases to be paired with an unconditioned stimulus for a number of times the occurrences of a conditioned response decrease or disappear. This is known as extinction.
Spontaneous recovery : In the classical conditioning paradigm, spontaneous recovery is the sudden reappearance of the conditioned response following a rest period after extinction.
Stimulus generalisation : In classical conditioning paradigm, stimulus generalisation is the tendency of the conditioned response to occur to stimulus similar to the conditioned stimulus.
Discrimination : In classical conditioning paradigm, discrimination refers to the condition where an organism learns to produce a conditioned response to one stimulus but not to another similar stimulus, as the latter has been systematically kept non-reinforced.
Counter conditioning : Counter conditioning is a replacement of an undesirable conditioned response by a desirable one, by changing the association of conditioned and unconditioned stimulus.
Systematic desensitisation : A therapeutic technique based on classical conditioning. The client is exposed to the phobic object or its image in graded stages, starting from a point where she is fully relaxed, and then guided progressively toward staying relaxed even in situations where she experienced intense fear.
Aversion therapy : A therapeutic technique used to modify undesirable habits. The client’s real or imagined undesirable behaviour is associated with an aversive or painful stimulus. It is expected that after repeated pairing the aversive response would be generated by the undesirable habit itself.
1.9 UNIT END QUESTIONS
Examine the role of reinforcement in classical conditioning.
Define and give examples of extinction and spontaneous recovery.
Differentiate between extinction and counterconditioning.
Differentiate between generalisation and discrimination in classical conditioning.
Discuss with suitable examples, the classical conditioning of psychopathology.
‘Systematic desensitisation is an example of application of classical conditioning in therapy’ - illustrate with example.
Discuss the criticisms of classical conditioning.
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1.10 SUGGESTED READINGS
Hall,C.S. and Lindzey, A. (1997). Theories of Personality , New York, Wiley Liebert, R. M. & Spiegler, M. D. (1987) Personality: Strategies and Issues. Homewood, IL: The Dorsey Press. Pervin, L. A. & John, O. P. (1997) Personality: Theory and Research. New York: John Wiley & Sons. Internet source : http:// www. Youtube.com/watch? v=CpolxEN54ho& feature=related.
1.11 ANSWERS TO SELF ASSESSMENT
QUESTIONS
Self Assessment Questions 1
- Ivan Petrovich Pavlov was a Russian physiologist. He is famous for his experiment on classical conditioning using dog’s salivary response.
- Classical conditioning is learning by association, whereby a neutral stimulus, by virtue of its occurrence in close time and space with a natural stimulus that gives rise to a natural response, becomes capable of eliciting that natural response, even in absence of the natural stimulus.
Correct answers are: i) both UCS and UCR and they are identical. ii) both UCS and CR and they are identical. iv) both UCR and CR but they are not identical
Self Assessment Questions 2
- a) True b) False c) False
- a) counter conditioning b) orange light
Self Assessment Questions 3
- a) emotions can be conditioned b) Joseph Wolpe c) pleasant stimuli
- i) Luncheon technique is a management technique based on classical conditioning principle. Here a business proposal is presented with a well arranged lunch or dinner party, so that the association of good food makes the key decision makers more inclined toward accepting the proposal. ii) Aversion therapy is a technique based on classical conditioning. Here, the undesirable behaviour which the therapist wants removed is paired with an aversive stimulus, so that the undesirable behaviour it self turns out to be aversive to the subject.
