Pavlov’s Experiment: A breakthrough in Conditioned Learning

Discovered by Ivan Pavlov, a Russian physiologist, Classical conditioning, also known as Pavlovian conditioning, inculcates learning through association. Pavlovian theory is a learning procedure that involves pairing a stimulus with a conditioned response.

Ivan Pavlov’s famous experiment conducted on his dogs found that objects or events could trigger a conditioned response. In this experiment Pavlov demonstrated how presence of a bowl full of dog food (stimulus) triggered an unconditioned response (salivation). But Pavlov noticed that the dogs started to associate his lab assistant with food; as he used to bring the food. Pavlov thus discovered that one can create learned and conditioned response.

Intrigued with his discovery, Pavlov then designed an experiment using a bell as a neutral stimulus. As he gave food to the dogs, he rang the bell. Then, after repeating this procedure, he rang the bell without providing food to the dogs. But just watching the bell being rung, the dogs’ mouth stated to fill with saliva. The result of the experiment was to develop a new conditioned response in the dog.

Classical Conditioning thus emphasizes the importance of learning from the environment and instincts. However, limiting learning to just environment and instincts underestimates the complexity of human behaviour.

Classical Conditioning theory being scientific is based on empirical evidence carried out by controlled experiments. For example, Pavlov (1902) showed how Classical Conditioning could be used to make a dog salivate to the sound of a bell.

Classical Conditioning is also an explanation of behaviour as it breaks down a complex behaviour into smaller stimulus-response units of behaviour.

Basic Principles of Classical Conditioning

Classical Conditioning is a form of learning whereby a Conditioned Stimulus (CS) becomes associated with an unrelated Unconditioned stimulus (US) to produce a behavioural response known as a Conditioned Response (CR). The conditioned response is the learned response to the previously neutral stimulus. The unconditioned stimulus is usually a biologically significant stimulus such as food or pain that elicits an unconditioned response (UR) from the start. The conditioned stimulus is usually neutral and produces no particular response at first, but after conditioning, it elicits the conditioned response.

Extinction is the decrease in the conditioned response when the unconditioned stimulus is no longer presented with the conditioned stimulus. When presented with the conditioned stimulus alone, the individual would show gradual weaker response, and finally no response. In classical- conditioning, thus, there is a gradual weakening and disappearance of the conditioned response.

Related to this, spontaneous recovery refers to the return of a previously extinguished conditioned response following a rest period. Research has found that with repeated extinction/recovery cycles, the conditioned response tends to be less intense with each period of recovery.

Emergence of Behaviourism

Behaviourism, also known as behavioural psychology, is a theory of learning based on the idea that all behaviours are acquired through conditioning. Conditioning occurs through interaction with the environment. Behaviourists believe that our responses to environmental stimuli shape our actions.

According to this school of thought, behaviour can be studied in a systematic and observable manner regardless of internal mental states. According to this perspective, only observable behaviour considered -like cognitions, emotions, and moods — are far too subjective.

Strict behaviourists believed that any person can potentially be trained to perform any task, regardless of genetic background, personality traits, and internal thoughts (within the limits of their physical capabilities). It only requires the right conditioning.

Pavlov studied under Cardiovascular Physiologist — Carl Ludwig in Leipzig, Germany, and Gastrointestinal Physiologist — Rudolf Heidenhain in Breslau, Poland. With Heidenhain, he devised an operation in which he created an exteriorized “pouch” on a dog’s stomach and maintained nerve supply to properly study gastrointestinal secretions. He then spent two years at a laboratory in St. Petersburg, where he researched cardiac physiology and the regulation of blood pressure. Pavlov’s research also contributed to Hans Eysench’s personality theory of introversion and extroversion. Eysench built upon Pavlov’s research on dogs, hypothesizing that the differences in arousal that the dogs displayed was due to inborn genetic differences. Eysench then extended the research to human personality traits.

Pavlov’s research further led to the development of important behaviour-therapy techniques, such as flooding and desensitizing, for individuals who struggle with fear and anxiety. Desensitizing is a kind of reverse conditioning in which an individual is repeatedly exposed to the thing that is causing the anxiety. Flooding is similar in that it exposes an individual to the thing causing the anxiety, but it does so in a more intense and prolonged way.

Little Albert experiment: an experiment on Conditioning

The Little Albert experiment presents an example of how Classical Conditioning can be used to condition an emotional response. Around the age of 9 months, Watson and Rayner exposed the child to a series of stimuli including a white rat, a rabbit, a monkey, masks, and burning newspapers and observed the boy’s reactions. The boy initially showed no fear of any of the objects he was shown.

The next time Albert was exposed to the rat, Watson made a loud noise by hitting a metal pipe with a hammer. Naturally, the child began to cry after hearing the loud noise. After repeatedly pairing the white rat with the loud noise, Albert began to cry simply after seeing the rat.

Some practical examples for your understanding:

The influence of Classical Conditioning can be seen in responses such as phobias, disgust, nausea, anger, and sexual arousal. A familiar example is conditioned nausea, in which the sight or smell of particular food causes nausea as it must have caused stomach upset in the past. Similarly, when the sight of a dog has been associated with a memory of being bitten, the result may be a conditioned fear of dogs.

As an adaptive mechanism, conditioning helps shield an individual from harm or prepare them for important biological events, such as sexual activity. Thus, a stimulus that has occurred before sexual interaction comes to cause sexual arousal, which prepares the individual for sexual contact.

Shreya, a student of Year 13, IB at The British School, New Delhi, is a young blogger with passion for Psychology and technology. Being an avid reader, Shreya keeps enriching her mind by reading all the books about mind. Her area of focus is to incorporate new-age technology in the field of psychology to bring break-through improvements in mental- health and overall wellness of people. Aiming to reach her goals — one step at a time