Classical conditioning is a learning process where a subject learns to associate a certain stimulus with a specific response. It is an aspect of the school of thought called behaviourism, an approach to psychology that focuses on actions as opposed to thoughts or feelings and believes that an animal or human’s behaviour is shaped by their environment.
Classical conditioning is also known as Pavlovian conditioning after Ivan Pavlov, the Russian physiologist known for recording the most famous example of the process. While carrying out research into digestion in dogs, he observed that in addition to salivating when food was presented to them, they began to salivate on seeing the person who usually fed them. He hypothesised that if a stimulus was present every time the dogs were given food, in time they would come to associate the stimulus with food and would salivate in response to the stimulus alone. He began ringing a bell while feeding the dogs, and after repeating this process several times, he found that ringing the bell without presenting food was enough to cause the dogs to salivate, thus leading to the discovery of classical conditioning.
The process of classical conditioning involves an unconditioned stimulus, a conditioned stimulus, an unconditioned response and a conditioned response. The conditioned stimulus – the bell in Pavlov’s experiment – elicits no response before conditioning. After becoming associated with the unconditioned stimulus – the dogs’ food – it led to the conditioned response of the dogs salivating upon hearing the bell. Before classical conditioning, the dogs had only an unconditioned response; the automatic salivation when presented with food.
The way classical conditioning is carried out can vary. The most effective learning is gained through forward conditioning, a form of classical conditioning where the conditioned stimulus is presented before the unconditioned stimulus, signalling that the unconditioned stimulus will follow.
If the conditioned stimulus is continuously presented with no unconditioned stimulus, the subject can stop responding to the conditioned stimulus. This process is known as extinction. Extinction has parallels with habituation, where the subject stops reacting to certain stimuli after repeated exposure.