Classical conditioning PDF

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Classical conditioning...

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Classical Conditioning Module Details 1. Subject Name

Adult Education

2. Paper Name

Psychological Foundation

3. Module number

Module- 2.11

4. Module Name

Classical Conditioning

Content Outline 1. Objectives 2. What is classical conditioning 3. The classic experiment of classical conditioning 4. Basic concepts of classical conditioning 5. Application of classical conditioning 6. Summary

1.

Objectives At the end of the module, the learner will be able to, •

Define learning

•

Describe the pioneer experiment in classical conditioning.

•

Explain the concepts of classical conditioning.

•

Discuss the application of classical conditioning

2. What is classical conditioning Classical conditioning is a form of learning. Learning is defined as “relatively permanent change in behaviour due to practice or experience.” Classical conditioning is also known as Pavlovian conditioning.

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3. The classic experiment of classical conditioning Ivan Pavlov the Nobel Prize digestive

system

and

in

the

winner

Russian

physiologist

of

study

course

this

was

working

discovered

on

classical

conditioning.

In the classic experiment conducted by Pavlov the experimental animal was a dog. The experimental condition/procedure was as follows: The experimental dog was harnessed to a platform. A small surgery was done and tube was inserted to collect saliva. A bell was presented followed by food and saliva was collected after sighting of food by the dog. This pairing of bell and food was done for a number of trials and response of saliva was measured. After a few trials of this pairing it was noticed that saliva response was given by dog after the presentation of bell and before the presentation of food. This response (saliva) to bell was the learning and was termed as classical conditioning.

4. Basic concepts of classical conditioning In classical conditioning the terms and concepts used are as follows: Unconditioned stimulus (US): The stimulus that produces reflexive response that occurs automatically and is not learned. In the above example of experiment with dog, Food is unconditioned stimulus. Saliva is a reflex

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response to food and the animal does not learn to salivate at the sight of food. Other examples of unconditioned stimulus are puff of air for eye-blink response, and so on. Unconditioned response (UR): This is automatic unlearned response to the unconditioned stimulus. Therefore saliva is unconditioned response to food, Eye blink is unconditioned response to air-puff. Conditioned

stimulus

(CS): Is a neutral stimulus with reference to the

unconditioned response. Thus in the experiment on dog, the

bell

is

the

Conditioned stimulus since it is a neutral stimulus with respect to unconditioned response

i.e.

the

saliva.

The

meaning

of

neutral

is

that

it

does

not

automatically or reflexively produce the unconditioned response. The bell does not automatically produce saliva response in the dog. Conditioned response (CR): The response produced by conditioned stimulus is conditioned response. It

is

similar

to

Unconditioned

response

but

not

identical. Therefore in the dog experiment after a number of pairing of bell (CS) and Food(US), when bell alone is presented then if dog salivates then it is conditioned response. Thus this is a learned response

and not

a reflex

response to bell. The saliva as conditioned response is similar to saliva as unconditioned response but not identical, it may vary in intensity or other aspects. The temporal order of conditions presented in the classical conditioning experiment is as follows: CS(Bell)--------US(Food) -------------- UR(Saliva) After a number of trials of pairing of Bell and Food CS(Bell) --------------------------------- CR(Saliva) Thus when a CR is obtained after the presentation of CS (and before the presentation of US) then it is concluded that conditioning is established. Extinction:

After

conditioning

is

established

it

can

be

unconditioned

i.e.

extinguished by the following procedure. A number of trials are presented with CS alone without being paired with US. After a few trials with CS alone the CR will not be given by the organism. Thus no CR at the presentation of CS is called extinction. In the experiment on dog, after the bell (CS) is presented the dog salivates(CR)

and,

then

if

the

experimenter continues the trials with bell alone then after a few trials the response of salivation will stop at the ringing of the bell. This is extinction. Spontaneous

recovery:

When

extinction

takes

place

(no

CR

at

the

presentation of CS) then after a gap of sometime if the participant is brought back

to

the

same

experimental

situation

and

CS

is

presented

CR

may

spontaneously be given by the participant, it is called spontaneous recovery.

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So in the aforementioned example of the dog experiment, after extinction has taken place i.e. no saliva (CR) at the ringing of the bell (CS),If the dog is brought back to the experimental room and the bell is presented and the dog respond by salivating. This is known as spontaneous recovery. Stimulus generalization: When CR is given to another neutral stimulus that is similar to the original CS then it is known as stimulus generalization. In the example of dog experiment when the dog salivates to buzzer (a neutral stimulus that is similar to bell, the original CS) as well then it is known as stimulus generalization. a. Stimulus discrimination: It is opposite of generalization. In generalization CR is given not only to the original CS but also to the similar CS. In discrimination CR is given to only the original CS and not to any other similar CS. Thus in Dog’s experiment, CR is given only to bell and not to buzzer. This is done by pairing original CS i.e. the bell with Food and not pairing any other similar CS e.g. buzzer with US i.e. food. Higher order conditioning: In this type of conditioning once conditioning is established with original neutral CS(bell), then

this CS

(bell)is

paired

with

another CS(light) and CR is elicited. When CR is elicited for CS (2 i.e. light) without it being

paired with

US

(food)

then

it

is

called

higher

order

conditioning. In humans the higher order conditioning can occur at multilevel. For example Food is US and satiety is UR. Money can buy food, so the pairing of money(CS) with food(US) produces conditioning. Prestige (CS2) is paired with money(CS1) and produces first level higher order conditioning. Power(CS3) is paired with prestige(CS2) and produces second level higher order conditioning.

Forward Conditioning: When CS precedes US as generally is the case it is called forward conditioning. The fastest way of establishing conditioning is forward conditioning. Backward Conditioning: When US precede CS then it is backward conditioning. This type of conditioning is more difficult to establish. Delay conditioning: In this conditioning CS is presented and overlaps with presentation of US. Thus bell is presented first and continues till food is given. Trace conditioning: In this conditioning CS and US do not overlap. Therefore first bell is presented and after a few seconds it is stopped. Then food is presented. Thus there is a time gap between bell (CS) and food (US).

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Additional example of classical conditioning: If a puff of air is blown in the face our eyes automatically (reflexively) blink. We do not have to learn to blink when we have been stimulated with puff of air. Therefore in Classical conditioning term Puff of air is the unconditioned stimulus (US) that produces automatic response (eye blink) Eye blink is Unconditioned Response (UR) since it is automatic (unlearned) response to air puff. Now if we pair light with air puff a number of times and then if we find that eye blink response is give after the presentation of light and before air puff then we say classical conditioning is acquired. Now light is conditioned stimulus (since it is a neutral stimulus with respect to eye blink) Eye blinkresponse is conditioned response (since it is given in response to light and is a learned response). If the trials are given with only light and without air puff , then at one point of time eye blink response will be stopped. Therefore the extinction of learned response will take place. After a period of time if light is presented again and eye blink response occurs then it is spontaneous recovery. When eye blink response is given to similar light then it is stimulus generalization When eye blink response occurs only for the original light and no other light then it is stimulus discrimination. If we pair light with sound a number of times and finally when sound is presented and eye blink response occur it is higher order conditioning .

5. Application of Classical Conditioning: Conditioned Emotional Responses: J.B. Watson the famous American Psychologist from Behaviouristic school of Psychology, conducted the famous experiment on the little Albert.The experiment was as follows: There was a small white rabbit in the experimental field. Whenever little Albert approached the white rabbit a sudden loud noise was presented. In response to the sudden loud noise the child showed startles/ fear response and would start crying. Thus the pairing of rabbit and sudden loud noise continued for a few times, later it was seen that as soon as the child sighted the rabbit he would respond with fear and crying. This was the acquisition of conditioned emotional response. In the aforementioned example the sudden loud noise is the Unconditioned stimulus.

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Startle/fear response is the Unconditioned response. Sudden loud noise is the natural stimulus for startle/fear response. Rabbit is conditioned stimulussinceit is neutral with respect to startle/fear response When rabbit is paired with sudden loud noise and finally after presentation of only rabbit (conditioned stimulus)and before sudden loud noise if fear/crying response occurs then it is the acquisition (learning) of conditioned response . CS (Rabbit) +US (sudden loud noise) UR (Fear/crying) After a number of trials of CS and US pairing then if CS (rabbit) is presented and we get CR (fear/crying) Then the conditioned emotional response is acquired. Stimulus generalization: When any white furry object produces fear response then it is generalization of CER (conditioned Emotional Response) Let us take another real life example. Children when they are taken to the doctor/hospital for immunization shots they start crying right at the sight of the hospital building and sometimes even before that. This is a CER. Let us see how it is acquired. Injection (US) --------- Pain/crying (UR) Doctor (CS) + Injection (US) --------- Pain/crying (UR) After a few pairing of doctor and injection we get Doctor (CS) ----------------- Pain/Crying (CR) This is the acquisition of CER. Stimulus generalization will be fear/ crying response for anyone looking similar to doctor wearing a lab coat. Higher order conditioning: Continuing with the same example the higher order conditioning will be as follows: First order CER Doctor (CS1) ------------------------- Fear/crying (CR) Doctor’s office (CS2) + Doctor -------------- Fear/crying (CR) Second order CSR Doctor’s office (CS2) producing fear/crying (CR) This is how phobias in humans develop. The stimulus generalization and higher order conditioning takes place at multiple levels and the original pairing of CS1 with US producing the UR is forgotten. Let us take an example ofa client having phobia of closed places. When detailed case history was taken it was found that he was attacked with a knife in an attempt at robbery in a basement parking space. This is CER that took place as follows: Parking lot(CS) + Knife attack (US) -------- Fear/terror (UR)

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Parking lot (CS) ---------------------- Fear/terror (CR) Stimulus generalization to all closed spaces since the parking lot was in the basement that was closed. Thus fear/terror response is given to all the closed places through stimulus generalization. This type of response can be acquired with a single pairing of CS and US.

6. Summary: Classical conditioning is also known as Pavlovian conditioned, named after Russian Physiologist who first discovered it during his work in the field of digestive systems. The basic idea behind classical conditioning is as follows: If a neutral stimulus (CS) is paired with a natural stimulus (US) that produces a natural response (UR) then after a few trials of such pairing the neutral stimulus (CS) will produce the natural response (CR). When this happens it is called the acquisition of conditioned (learned) response. The acquired response can be extinguished by continuously not pairing the neutral stimulus (CS) with the natural stimulus (US), at one point the conditioned response will stop, this is extinction of conditioned (learned response) response. Other important concepts in classical conditioning are: Spontaneous recovery, stimulus generalization, stimulus discrimination, and higher order conditioning. One of the major applications of classical conditioning is -conditioned emotional response. The pioneer work in this field was done by J.B.Watson. Once it is known that our emotional responses are conditioned,then principles of classical conditioned can be used to un-condition them. This is done through behaviour modification techniques.

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