Concept of Pavlov’s Dogs Experiment And Pavlovian Conditioning Response

Concept of Pavlov’s Dogs Experiment And Pavlovian Conditioning Response

 During the 1890s, Ivan Pavlov was a Russian physiologist who was researching salivation in dogs as a response to being fed. While the dogs were being fed, he used a small test tube to measure the saliva by inserting it into their cheeks. He predicted that the dogs would salivate when the food was in front of them, but he realized that the salivation actually started when the dogs heard the footsteps of his assistant. The salivation was not only a result of the food being served, but of the sound of the footsteps that the dogs associated with being fed. This is how classical conditioning was discovered. Pavlov had the idea that dogs do not need to learn certain things, such as salivating when they see food. He said these reflexes are hard-wired into dogs. He coined the dog’s food as an unconditioned stimulus and the salivation as an unconditioned response – this response did not require any learning on the dog’s part.

Ivan Pavlov (1849–1936) was a Russian psychologist interested in animal and human learning who developed the concept of conditioning to describe the psychological processes of learning. He won the Nobel Prize for Medicine in 1904. Pavlov draws the distinction between an unconditioned (instinctive) and conditioned (environmental and learnt) reflex in response to a stimulus.

Life and Career of Ivan Pavlov

 Ivan Pavlov (26 September 1849 – 27 February 1936) was a Russian and Soviet experimental neurologist and physiologist. In 1904, Pavlov was awarded the Nobel Prize in Physiology or Medicine.

Ivan Pavlov was born on 26 September 1849, in Ryazan, Russia. He came from a humble background. His father, Peter Dmitrievich Pavlov, was a priest, and his mother, Varvara Ivanovna Uspenskaya, was the daughter of a priest.

Ivan Pavlov attended the Ryazan Ecclesiastical Seminary, where he initially prepared for a religious career. Later, he enrolled at the University of St. Petersburg (now St. Petersburg State University), where he studied natural sciences and graduated in 1875.

He continued his education at the Imperial Medical Academy of St. Petersburg, where he earned his doctorate in 1883.

After completing his education at the University of St. Petersburg and the Imperial Medical Academy of St. Petersburg, Pavlov began his scientific career by conducting research on the physiology of the digestive system.

Pavlov’s early work focused on studying the digestive processes in dogs. He is particularly known for his investigations into the salivary reflex, which laid the foundation for his later research on conditioning.

One of Pavlov’s most famous contributions to science was his series of experiments involving dogs, where he explored the concept of conditioned reflexes. He observed that dogs could be trained to associate a neutral stimulus, such as the sound of a bell, with the presentation of food. This research led to the development of the theory of classical conditioning, where a previously neutral stimulus can evoke a response after being paired with a naturally occurring stimulus.

Pavlov published numerous papers and books throughout his career, including his seminal work, “Conditioned Reflexes: An Investigation of the Physiological Activity of the Cerebral Cortex,” which was published in 1927.

His research on conditioned reflexes and the role of the brain in learning and behavior had a profound impact on the fields of psychology and physiology.

Pavlov’s work in the early 20th century had a major influence on the development of behaviorism in psychology, which emphasized the study of observable behavior and the role of conditioning in learning.

Ivan Pavlov passed away on 27 February 1936, in Saint Petersburg, Russia.

Award and Legacy

In 1904, Pavlov was awarded the Nobel Prize in Physiology or Medicine for his research on the physiology of digestion, particularly his studies on the digestive glands. This Nobel Prize recognized his significant contributions to the field of physiology.

Ivan Pavlov’s legacy is enduring. His research on classical conditioning and the concept of conditioned reflexes remain fundamental in psychology and continue to be studied and applied in various fields, including education, therapy, and animal training.

 One of the most revealing studies in behavioral psychology was carried out by Russian physiologist Ivan Pavlov (1849-1936) in a series of experiments today referred to as ‘Pavlov’s Dogs‘. His research would become renowned for demonstrating the way in classical conditioning (also referred to as Pavlovian conditioning) could be used to cultivate a particular association between the occurrence of one event in the anticipation of another.

Pavlov’s dog experiments played a critical role in the discovery of one of the most important concepts in psychology: Classical conditioning.

While it happened quite by accident, Pavlov’s famous experiments had a major impact on our understanding of how learning takes place as well as the development of the school of behavioral psychology. Classical conditioning is sometimes called Pavlovian conditioning.

What is Classical Conditioning?

Classical conditioning is a learning theory that interprets learning as an associative process where learning is a new association or connection that is formed between a stimulus and a response. It is developed by Ivan Pavlov, a Russian psychologist.

Basic Elements in Classical Conditioning

To understand better, how classical conditioning works, let us first understands, the key elements used by Pavlov in his research.

Unconditioned Stimulus (UCS or US)

The meat powder was the unconditioned stimulus (UCS or simply the US) in Pavlov’s experiment because it can elicit the natural and spontaneous response of salivation without any learning. The dog does not have to be trained to react to the unconditioned stimulus.

Unconditioned Response (UCR or UR)

Pavlov called the salivation in response to food in the dog’s mouth an unconditioned response (UCR). It is an automatic reaction that is an inborn, natural process. For example, touching a hot stove causes us to jerk our hands away, a puff of air causes our eyes to blink, a high temperature causes sweating, etc.

These UCRs are reflexes in which all organisms come equipped by nature with many built-in responses, which generally have survival value. Food in the dig’s mouth automatically and unconditionally triggered a dog’s salivary reflex. Thus Pavlov called the food stimulus an “Unconditioned Stimulus”, and salivation as a response to food an “Unconditioned Response”.

Neutral Stimulus (NS)

At the beginning of the conditioning process in the laboratory setting when responses were not established Pavlov called light, bell, etc. a “neutral stimulus”, because they did not initially cause the dog to secrete saliva.

Conditioned Stimulus (CS)

A neutral stimulus acquires the ability to elicit a salivation response after being paired with an unconditioned stimulus. When the dog associates the NS with the UCS (food) the NS is transferred into a conditioned stimulus (e.g. light, bell), that can elicit a response (salivation) similar to UCS.

Conditioned Response (CR)

Salivation in response to the CS (light, bell) is known as the conditioned response (CR). Thus, the previously neutral stimulus has now triggered the salivation, called the conditioned response (CR). When the CS elicits CR, the classical condition has been established.

Steps in Classical Conditioning

Classical conditioning aims to convert a neutral stimulus (bell) into a conditioned stimulus that will produce a conditioned response. To complete the classical conditioning process, it is needed to complete three steps.

Step #1 Before Conditioning

Before conditioning is the first step in the classical conditioning process. Where the unconditioned stimulus (food, say meat) produces an unconditioned response (salivation) in the dog’s mouth.And, also in this stage, Pavlov used a bell, which is called a neutral stimulus as it does not affect the dog’s salivation activities. Or, when the bell rings the dog does not give any response.

Step #2 During Conditioning

In this stage, Pavlov combined the neutral stimulus (bell) with the food (that becomes a conditioned stimulus). Whenever Pavlov went to give food to the dog, he used to ring the bell, first and gave food to the dog.

It is where the dog is understanding ringing the bell is a sign for getting food.

Step #3 After Conditioning

In this stage, the neutral stimulus (bell) is termed a conditioned stimulus. And, whenever the bell rings the dog gives a conditioned response. It is where the dog understood ringing the bell is a sign of getting food, and whenever the Pavlov rings the bell, the dog came to him either he rings to give him food or just for fun, or nothing.

Principles in Classical Conditioning

Pavlov revealed the five key principles in his classical conditioning theory of learning. Let’s understand how these principles work.

Acquisition

The acquisition is the training stage during which the animal is learning the stimulus-response relationship. For example, the association between the CS and the US is the acquisition stage of conditioning.

Pavlov and his associates had to confront the question of timing. How much time should elapse between presenting the neutral stimulus (light, bell, tone, touch, etc.) and unconditioned stimulus, and which one is to be presented first? They found that a very little time gap and presenting the neutral stimulus first is effective for a perfect conditioning experiment.

Several factors influence the acquisition of conditioned response, among them, being the order in which the CS and UCS are presented, the intensity of the UCS, the number of times the CS and UCS are paired, and the time relations between CS and US are the important agents in conditioning.

Extinction

Extinction is the general term for the reduction and elimination of behaviors learned earlier in classical conditioning. Once CR has been acquired after conditioning, what happens if the CS (bell) occurs repeatedly without the UCS (food)? Pavlov found that when he sounded the bell again and again without presenting food, the dog salivated less and less. The number of drops of saliva produced gradually decreased each time. It is diminished responding that occurs when the CS (tone) is no longer the signal associated with the UCS (food).

In the acquisition or training phase, the CS and UCS are paired together and lead to the UCR. This pairing eventually leads to the production of the CR following CS. Repeated presentation of the CS alone leads to extinction.

Spontaneous Recovery

Spontaneous recovery is the reappearance of an extinguished CR after the passes of time. In spontaneous recovery, the learner seems to “forget” that extinction has occurred. In Pavlov’s study, only the CS (bell) has been presented to the dog several times during its extinction session. The CR (salivation) decreases until it appears that the dog is not salivating at all. Then, suppose that the day after the extinction of CR, the dog is brought back to the laboratory and the tone (CS) is presented with food (US), which causes the dog to begin salivating again. Pavlov called this phenomenon spontaneous recovery. The phenomenon of spontaneous recovery shows that extinction does not completely erase conditioning.

Spontaneous recovery is not limited to laboratory experiments as it occurs in real-life situations as well. Suppose, you went to a family picnic last winter and you lost your movie camera. Now, a full year later your family wants to organize a picnic again, and you are scared to take your new movie camera. Your fear of losing the camera has returned (i.e. spontaneous recovery). It warns you of possible loss again and to be cautious.

Stimulus Discrimination

Discrimination is the ability to distinguish between a conditioned stimulus and other stimuli that do not signal an unconditioned stimulus. In discrimination occurrences of responses only occur to a specific CS. For example, in Pavlov’s study, the dog learned to respond to a sound of only a particular bell, paired the specific tone with an unconditioned stimulus, or used another stimulus, such as light without the unconditioned stimulus. The dog showed responses only to the specific bell because that bell was conditioned with food. The dog did not respond to light, which highlights discrimination.

Discrimination serves as a survival skill in an organism’s life. For example, if an herbivorous organism does not easily distinguish between edible and unedible vegetation, the organism may eat poisonous plants and eventually dies.

Stimulus Generalization

Generalization is the tendency to respond to stimuli similar to the original conditioned stimulus. In Pavlov’s experiment even though the dogs were conditioned to salivate in response to a specific bell (CS), they also salivated when slight changes in the sound of the bell were made trough not quite so much, when other tones of the bell were presented, like the sound of a buzzer, or the beat of the metronome. In other words, there was an occurrence of responses (salivation) to stimuli that are similar to CS.

Examples

Example 1. Human Conditioning: Thinks of a food smell that makes you remember a pleasant memory, e.g. fresh, luscious orange pickle (Suntala Sadheko). Does your mouth water? The food you enjoy is a UCS. Salivation is the UCR that occurs when the food is in your mouth. The CS is the name of the food such as Suntala Sadheko, and CR is the salivation that occurs when you hear the name of your favorite food.

Example 2. Somebody puff’s on your eyes for the first time unknowingly and you blink, the second time when you that person, again you blink even it is not puffed.

Process of conditioning

The entire process of conditioning can be explained like this:

Food——————-Salivation

Bell—-Food————-Salivation

REPEAT

Bell———————Salivation

Laws of Conditioning

Classical Conditioning is based on three laws:

1. If the Conditioned Stimulus ( Bell ) is given after the Unconditioned Stimulus ( Food ) ,there will be no conditioning.
2. If the Conditioned Stimulus ( Bell ) is given before the Unconditioned Stimulus ( Food ) ,the  conditioning will sure to take place.
3. If the Conditioned Stimulus ( Bell ) and the Unconditioned Stimulus ( Food ) ,is given simultaneously, the Conditioning may or may not take place.

What is Pavlov’s Dogs Experiment?

Ivan Pavlov’s dogs experiment is an experiment that took place in the 1890s in which the Russian physiologist surgically implanted small tubes into the cheeks of dogs to measure the buildup of saliva that took place under a variety of conditions.

Pavlov’s dogs experiment came about as part of an accidental discovery. Pavlov had at the time been conducting research experiments into the dogs’ gastric systems. As part of this research, Pavlov and his assistants would enter the room where the dogs were housed with a variety of edible and non-edible items, with the intention of measuring the amount of saliva that each dog produced when each item was placed in front of them.

Pavlov prediction that the dogs would salivate when presented with edible items was soon proved correct. This represents an unconditioned response in the animals, in which the sight and smell of the food causes them to salivate. Pavlov couldn’t have predicted what happened next.

Pavlov’s Dog: A Background

How did experiments on the digestive response in dogs lead to one of the most important discoveries in psychology?

While studying digestion in dogs, Pavlov noted an interesting occurrence: His canine subjects would begin to salivate whenever an assistant entered the room.

The concept of classical conditioning is studied by every entry-level psychology student, so it may be surprising to learn that the man who first noted this phenomenon was not a psychologist at all.

In his digestive research, Pavlov and his assistants would introduce a variety of edible and non-edible items and measure the saliva production that the items produced.

Salivation, he noted, is a reflexive process. It occurs automatically in response to a specific stimulus and is not under conscious control.

However, Pavlov noted that the dogs would often begin salivating in the absence of food and smell. He quickly realized that this salivary response was not due to an automatic, physiological process.

Pavlov’s Theory of Classical Conditioning

Based on his observations, Pavlov suggested that the salivation was a learned response. Pavlov’s dog subjects were responding to the sight of the research assistants’ white lab coats, which the animals had come to associate with the presentation of food.

Unlike the salivary response to the presentation of food, which is an unconditioned reflex, salivating to the expectation of food is a conditioned reflex.

Pavlov then focused on investigating exactly how these conditioned responses are learned or acquired. In a series of experiments, he set out to provoke a conditioned response to a previously neutral stimulus.

He opted to use food as the unconditioned stimulus, or the stimulus that evokes a response naturally and automatically. The sound of a metronome was chosen to be the neutral stimulus.

The dogs would first be exposed to the sound of the ticking metronome, and then the food was immediately presented.

After several conditioning trials, Pavlov noted that the dogs began to salivate after hearing the metronome. “A stimulus which was neutral in and of itself had been superimposed upon the action of the inborn alimentary reflex,” Pavlov wrote of the results.

“We observed that, after several repetitions of the combined stimulation, the sounds of the metronome had acquired the property of stimulating salivary secretion.”

In other words, the previously neutral stimulus (the metronome) had become what is known as a conditioned stimulus that then provoked a conditioned response (salivation).

To review, the following are some key components used in Pavlov’s theory:

• Conditioned stimulus: This is what the neutral stimulus becomes after training (i.e., the metronome was the conditioned stimulus after Pavlov trained the dogs to respond to it)
• Unconditioned stimulus: A stimulus that produces an automatic response (i.e., the food was the unconditioned stimulus because it made the dogs automatically salivate)
• Conditioned response (conditioned reflex): A learned response to previously neutral stimulus (i.e., the salivation was a conditioned response to the metronome)
• Unconditioned response (unconditioned reflex): A response that is automatic (i.e., the dog’s salivating is an unconditioned response to the food)

Pavlov’s Dog Experiment

Pavlov (1902) started from the idea that there are some things that a dog does not need to learn. For example, dogs don’t learn to salivate whenever they see food. This reflex is ‘hard-wired’ into the dog.

Pavlov showed that dogs could be conditioned to salivate at the sound of a bell if that sound was repeatedly presented at the same time that they were given food.

Pavlov and his studies of classical conditioning have become famous since his early work between 1890-1930. Classical conditioning is “classical” in that it is the first systematic study of the basic laws of learning (also known as conditioning).

Pavlov’s dogs were individually situated in secluded environments, secured within harnesses. A food bowl was positioned before them, and a device was employed to gauge the frequency of their salivary gland secretions.

The data from these measurements were systematically recorded onto a rotating drum, allowing Pavlov to meticulously monitor the rates of salivation throughout the course of the experiments.

First, the dogs were presented with the food, and they salivated. The food was the unconditioned stimulus and salivation was an unconditioned (innate) response. (i.e., a stimulus-response connection that required no learning).

Unconditioned Stimulus (Food) > Unconditioned Response (Salivate)

In his experiment, Pavlov used a metronome as his neutral stimulus. By itself, the metronome did not elicit a response from the dogs.

Neutral Stimulus (Metronome) > No Response

Next, Pavlov began the conditioning procedure, whereby the clicking metronome was introduced just before he gave food to his dogs. After a number of repeats (trials) of this procedure, he presented the metronome on its own.

As you might expect, the sound of the clicking metronome on its own now caused an increase in salivation.

Conditioned Stimulus (Metronome) > Conditioned Response (Salivate)

So the dog had learned an association between the metronome and the food and a new behavior had been learned.

Because this response was learned (or conditioned), it is called a conditioned response (and also known as a Pavlovian response). The neutral stimulus has become a conditioned stimulus.

Temporal contiguity

Pavlov found that for associations to be made, the two stimuli had to be presented close together in time (such as a bell).

He called this the law of temporal contiguity. If the time between the conditioned stimulus (bell) and the unconditioned stimulus (food) is too great, then learning will not occur.

‘Unconditioning’ through experimental extinction

In extinction, the conditioned stimulus (the bell) is repeatedly presented without the unconditioned stimulus (the food).

Over time, the dog stops associating the sound of the bell with the food, and the conditioned response (salivation) weakens and eventually disappears.

In other words, the conditioned response is “unconditioned” or “extinguished.”

Spontaneous recovery

Pavlov noted the occurrence of “spontaneous recovery,” where the conditioned response can briefly reappear when the conditioned stimulus is presented after a rest period, even though the response has been extinguished.

This discovery added to the understanding of conditioning and extinction, indicating that these learned associations, while they can fade, are not completely forgotten.

Generalization

The principle of generalization suggests that after a subject has been conditioned to respond in a certain way to a specific stimulus, the subject will also respond in a similar manner to stimuli that are similar to the original one.

In Pavlov’s famous experiments with dogs, he found that after conditioning dogs to salivate at the sound of a bell (which was paired with food), the dogs would also salivate in response to similar sounds, like a buzzer.

This demonstrated the principle of generalization in classical conditioning.

However, the response tends to be more pronounced when the new stimulus closely resembles the original one used in conditioning.

This relationship between the similarity of the stimulus and the strength of the response is known as the generalization gradient.

This principle has been exemplified in research, including a study conducted by Meulders and colleagues in 2013.

Impact Of Pavlov’s Research

Ivan Pavlov’s key contribution to psychology was the discovery of classical conditioning, demonstrating how learned associations between stimuli can influence behavior.

His work laid the foundation for behaviorism, influenced therapeutic techniques, and informed our understanding of learning and memory processes.

1. Behaviorism:Pavlov’s work laid the foundation for behaviorism, a major school of thought in psychology. The principles of classical conditioning have been used to explain a wide range of behaviors, from phobias to food aversions.
2. Therapy Techniques:Techniques based on classical conditioning, such as systematic desensitization and exposure therapy, have been developed to treat a variety of psychological disorders, including phobias and post-traumatic stress disorder (PTSD).

   In these therapies, a conditioned response (such as fear) can be gradually “unlearned” by changing the association between a specific stimulus and its response.

3. Little Albert Experiment: The Little Albertexperiment, conducted by John B. Watson in 1920, demonstrated that emotional responses could be classically conditioned in humans. A young child, “Little Albert,” was conditioned to fear a white rat, which generalized to similar objects.
4. Educational Strategies:Educational strategies, like repetitive learning and rote memorization, can be seen as applications of the principles of classical conditioning. The repeated association between stimulus and response can help to reinforce learning.
5. Marketing and Advertising:Principles from Pavlov’s conditioning experiments are often used in advertising to build brand recognition and positive associations.

   For instance, a brand may pair its product with appealing stimuli (like enjoyable music or attractive visuals) to create a positive emotional response in consumers, which then gets associated with the product.

Pavlov’s discovery of classical conditioning remains one of the most important in psychology’s history.

In addition to forming the basis of what would become behavioral psychology, the classical conditioning process remains important today for numerous applications, including behavioral modification and mental health treatment.

Principles of classical conditioning are used to treat the following mental health disorders:³

• Anxiety
• Depression
• Obsessive-compulsive disorder (OCD)
• Panic attacks and panic disorder
• Phobias
• Substance use disorders

For instance, a specific type of treatment called aversion therapy uses conditioned responses to help people with anxiety or a specific phobia.

A therapist will help a person face the object of their fear gradually—while helping them manage any fear responses that arise. Gradually, the person will form a neutral response to the object.⁴

Pavlov’s work has also inspired research on how to apply classical conditioning principles to taste aversions. The principles have been used to prevent coyotes from preying on domestic livestock and to use neutral stimulus (eating some type of food) paired with an unconditioned response (negative results after eating the food) to create an aversion to a particular food.

Unlike other forms of classical conditioning, this type of conditioning does not require multiple pairings in order for an association to form. In fact, taste aversions generally occur after just a single pairing. Ranchers have found ways to put this form of classical conditioning to good use to protect their herds.

In one example, mutton was injected with a drug that produces severe nausea. After eating the poisoned meat, coyotes then avoided sheep herds rather than attack them.

 Frequently Asked Questions

Why were Pavlov’s experiments so important to psychology?

The most significant contribution Pavlov gave to the discipline of psychology is that behavior is learned, and so he initiated the school of behaviorism in psychology.

What is Pavlov known for?

Pavlov is known for his experiments with dogs, showing that classical conditioning is possible when you pair two unrelated stimuli to produce a conditioned response.

What is the main principle in Pavlov’s theory?

The main principle in Pavlov’s theory is that an association can be drawn between two unrelated stimuli when presented at the same time or within a short time span.

What are the 3 stages of classical conditioning?

Before acquisition is the first stage and it is when the researcher understands the unconditioned stimuli and response, such as food and salivation. Acquisition is the second stage and it refers to the repeated pairing of the neutral stimulus with the conditioned stimuli. The after acquisition stage is when the neutral stimuli becomes the conditioned stimuli to produce the conditioned response.

What did Pavlov’s experiment prove?

Pavlov’s experiment proved that classical conditioning is possible in dogs, and that behavior is learned over time. He showed that it is possible to associate two unrelated stimuli.

What is the Pavlov dog experiment?

The Pavlov dog experiment is a key psychological experiment carried out in the early 20th century to show that classical conditioning is possible.

Aditi Singh
BA Applied Psychology Hons- Final Year,
Amity University, Noida

Compiled  & Shared by- Team, LITD (Livestock Institute of Training & Development)

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