Classical Conditioning

People often like to think they control their behaviour. But the truth is, external forces often condition our reactions, sometimes without us even being aware of it. Suppose you are scared of thunder. Every time you see a bolt of lightning, you might wince in expectation of thunder noise. That conditioned response is what’s called in psychology classical conditioning.

The Russian physiologist Ivan Pavlov discovered classical conditioning. Pavlov’s dogs inspired his experiment (1897) when he noticed the dogs salivating as soon as his assistant opened their cage doors because they associated open doors with receiving food.

Pavlov (1897) decided to test this hypothesis by conducting a new experiment in which each time the dogs were given food (stimulus 1), a bell sounded (stimulus 2), and the dogs slowly learned that the ringing of a bell was synonymous with food (new learned response). He observed and investigated the factors that can influence the strength and speed of learning by association and how they can provide explanations for some behaviours in humans, such as neurosis.

What is classical conditioning in psychology?

First, let's untangle the definition of classical conditioning.

According to John Watson (1913), classical conditioning explains all aspects of human psychology based on Pavlov’s findings and observations.

Pavlov’s classical conditioning of dogs, Katarina Gadže, StudySmarter Originals (Made in Canva)

Pavlov's classical conditioning research

In the 1890s, Pavlov studied salivation in dogs as an expectant response to being fed. He placed a small tube in each dog’s cheek to measure the amount of saliva when they were being fed. He expected the dogs to salivate at the sight of food, but instead, they salivated at the sound of the footsteps of his assistant, who was in charge of feeding them. He found that the dogs elicited a similar response to anything (lab assistant) paired with food. Pavlov researched this scientific discovery for many years.

Key terms in classical conditioning

Pavlov’s classical conditioning experiment

Pavlov based his study on the idea that some responses in dogs are innate and not learned. For example, dogs salivate naturally at the sight of food; they do not learn this response because it is naturally wired into them. Pavlov concluded from this observation that the unconditioned stimulus is the food, which leads to an unconditioned response, the dog’s salivation.

The unconditioned stimulus is food → The unconditioned response is salivation.

Pavlov strapped the dog into a harness attached to an apparatus that measured the rate and amount of salivation in three stages.

Neutral stimulus (bell) → No conditioned response.

2. He again measured the saliva when giving food to the dog.

3. Pavlov measured saliva when he rang the bell and presented the food at the same time.

These steps were repeated several times to condition the dogs to learn this association. The dog’s saliva levels were high after this conditioning with just the ringing of the bell, but without food. This step was crucial to measure the strength of the learned response. The neutral stimulus now became the conditioned stimulus.

Conditioned stimulus (bell) → Conditioned response (salivation).

Evaluation of classical conditioning

Pavlov greatly contributed to the theory of classical conditioning, which many researchers replicated after him. Although Pavlov’s theory formed the basis of classical conditioning, researchers who came after him added some important arguments for and against this theory.

• The theory of classical conditioning is considered scientific because Pavlov showed that it provided empirical evidence through a controlled experiment.
• John Watson (1913), in his Little Albert experiment (little Albert was conditioned to fear a rat), showed that classical conditioning explains all aspects of human psychology based on Pavlov’s findings and observations.
• Pavlov’s experiment supports the claim that our learning depends mainly on our environment. He rules out the possibility that we can learn some behaviours through the interaction of nature (biological) and the environment (cultivated).
• Classical conditioning is easily tested in a controlled laboratory setting. However, it may not apply to and explain complex human behaviours such as problem solving and memory.
• Classical conditioning is deterministic, however, in that it constrains the individual’s free will with respect to the response to be learned, just as little Albert had to learn to fear a rat in John Watson’s experiment (1913).