Explain the Pavlovian conditioning reflex in simple terms

1 Introduction

This learning text explains the basic principles of classical conditioning or signal learning. This is an important approach to explaining learning processes, which was first described by Ivan Pavlov. In the text we first explain Pavlov's experiments with dogs, then work out the laws of classical conditioning and explain to what extent the model can be transferred to humans. Our text is supported by a computer simulation of the Pavlovian dog; the user of this offer has the opportunity to repeat Pavlov's experiments. The simulation also offers the possibility of monitoring the learning success.

2. Classical conditioning

Classical conditioning or signal learning is considered a basic form of learning, it is also called the "easiest way of learning" (Nolting and Paulus, Learning Psychology - An Introduction and Guide 67). This type of learning is based on innate reflexes such as B. the blinking of the eye, the secretion of saliva or the flight reflex.

The Russian physiologist and Nobel Prize winner Ivan Pavlov (1849-1936) was one of the first to describe the phenomenon of classical conditioning. Pavlov studied the dog's digestive system. He knew that dogs react with increased production of saliva in their mouths at the sight and smell of food. However, he observed that certain other stimuli, such as e. B. the sight of the food bowl provoked the same reaction in a dog. Ivan Pavlov then asked himself whether this phenomenon could also be repeated experimentally, which he tested in a series of experiments on dogs.

Situation before the experiment:

Dogs react to the sight of food with increased salivation. This is a natural, innate reflex. The food stimulus, which is also referred to as an unconditioned stimulus or unconditioned stimulus (UKS), triggers the salivary response called the unconditioned response (UR).

Food (unconditioned stimulus / stimulus, UKS) -->Salivation (unconditioned response, UR)

Test procedure:

Pavlov used a bell in his experiments, which was a neutral stimulus for the dog, to which the dog naturally did not react with salivation.

Bell tone (neutral stimulus) -->No increased salivation

Pavlov arranged his experiment in such a way that the bell rang immediately before the feed was administered. The test animal reacted to the sight or smell of the food with increased salivation.

Bell (neutral stimulus) and food (unconditioned stimulus, UKS) -->Salivation (unconditioned response, UR)

After Pavlov had repeated the process a few times, it was enough if only the bell rang. Even without the subsequent administration of the feed, there was increased saliva production.

(Pavlov's experimental arrangement for studying the conditioned reflex)


Situation after the experiment:

What happened? Although the ringing was originally a neutral stimulus and had nothing to do with the food itself, after the attempt it reliably led to increased secretion of saliva. The neutral stimulus had become a conditioned stimulus or stimulus (KS), which led to the conditioned response salivary flow.

Bell signal (conditioned stimulus / stimulus, KS) --> Salivation (Conditioned Response, KR)

In the experiment described, the dog has learned to link a neutral stimulus to an involuntary reaction. So through the classical conditioning reactions to certain stimuli are learned, it is therefore also counted among the stimulus-reaction theories. Innate behavior forms the basis for this type of learning.

3. Law of contiguity

We have shown that neutral stimuli can be linked to innate behavior. But does this connection also work if six hours pass between the ringing and showing the food?

In our example, this connection is not possible, the dog will not be able to recognize a connection between food and ringing, as there is no contiguity of the stimuli. As a rule, conditioning can only occur if the neutral stimulus and the unconditioned stimulus (UKS) occur reasonably close to one another. If one leaves a longer time interval between the UKS and the neutral stimulus, the conditioning is made difficult or impossible.

4. Order of stimuli

Whether conditioning occurs does not only depend on the chronological sequence of the stimuli: the neutral stimulus must occur before the UKS so that stable conditioning can develop.

5. Absorbance

A learned, conditioned reaction does not have to be permanent. If z. B. if a longer series of the conditioned stimulus (KS) bell is offered without connection with the unconditioned stimulus food, then the conditioned salivary flow reaction is weakened or completely extinguished. This process is known as extinction. If KS and UKS are offered again after a pause, the conditioned reaction occurs again (cf. Lück [and others], Introduction to Psychology 140-145).

Even if the coupling of conditioned and unconditioned stimuli is not repeated from time to time, the conditioned response is weakened or extinguished.

6. Generalization

The conditioned salivation response can also be caused by other stimuli that are similar to the originally conditioned ringing stimulus. A similar sounding tone from another bell will produce the same reaction. This process is known as stimulus generalization; similar stimuli are associated with one and the same reaction.

7. Transferability of the model to humans

Today the prevailing opinion is that the theory of classical conditioning can only explain the learning of very simple behaviors. It is often criticized that it does not do justice to the complexity of human behavior. Kieffer [u. a.] state, however, that classical conditioning "[...] cannot be completely dismissed as inadequate for the occurrence of complex social behaviors" (Kieffer [et al.], Introduction to Psychology 206). The American psychologist John B. Watson (1878-1958) showed in an experiment that one can classically condition human fear reactions:

"[The] [...] 11-month-old boy ('Albert') [was] shown a white mouse. The child showed no fear, crawled up to her and wanted to play with her. However, his approach behavior was followed by a loud bang ( unconditioned stimulus), which triggered a startle reaction (unconditioned reaction). The boy immediately began to cry. Further approximations were always connected with the same consequence. Finally, it was sufficient to show the child the white mouse (as a stimulus that has meanwhile been conditioned), to arouse fear and horror in him "(Mietzel after Wawrinowski, Basic Course Psychology 76). The child later generalized this fear to other fur animals or men with beards.

In cases of social behavior disorders that are associated with fear reactions, it is therefore possible to successfully resort to the classic conditioning model for treatment. Behavioral therapy has done the same for the treatment of such disorders.

Wawrinowski even succeeds in deriving pedagogical consequences from classical conditioning. He is of the opinion that desirable behavior should be combined with pleasant reactions, whereas undesirable behavior should be inhibited by not allowing needs to be satisfied (Basic course in psychology 77).

8. Simulation of the Pavlovian dog

With the simulation, you have the opportunity to repeat Pavlov's experiment, and the program also offers the option of monitoring your learning success. To use the simulation, the Shockwave plug-in must be installed.