Classical Conditioning

Introduction:

In early 1900s Russia, Ivan Pavlov was studying how dogs’ salivation helps them to digest food when he noticed that they would sometimes salivate before they got food. Instead of just thinking they were hungry, he realised they had associated food with another stimulus, such as the sound of the door opening.

Pavlov started to experiment:

  1. Whenever Pavlov gave his dogs food, he would ring a bell. After repeating this procedure several times, Pavlov then tried bringing the bell without giving the dogs any food. The bell alone caused salivation.

  2. When dogs see food, they salivate. This is an automatic, unlearned response- a reflex. The food is an unconditioned stimulus (UCS) and salivation is an unconditioned response (UCR)

  3. The bell had become a conditioned stimulus (CS), and salivation had become a conditioned response (CR)

Before conditioning:

  1. A certain stimulus, e.g food (unconditioned stimulus)

    Triggers:

  2. A natural reflex, e.g salivation (unconditioned response)

During conditioning:

  1. UCS repeatedly presented with another stimulus, e.g a bell (neutral stimulus)

    Triggers:

  2. Salivation (Unconditioned response)

After conditioning:

  1. Over time the bell presented by itself (Conditioned stimulus)

    Triggers:

  2. Salivation (Conditioned response)

He later made the dogs associate food with lights and other abstract stimuli. This process of learning can be applied to human development:

  • Having its needs dealt with and gaining comfort naturally makes a baby happy. It hasn’t learnt to be happy. It’s an inborn reflex

  • So, comfort is an unconditional stimulus (UCS) that produces happiness- an unconditioned response (UCR)

  • The baby’s mother will talk to it while she feeds it and changes its nappy, etc. So, the baby hears its mother’s voice every time it’s made comfortable and happy

  • The sound of its mother’s voice is paired with having needs met and being comfortable (UCS), so the mother’s voice becomes a conditioned stimulus (CS)

  • Eventually, the sound of the mother’s voice alone will make the baby feel happy, even when it isn’t paired with having its needs met. The CS (voice) now causes a conditioned response (CR)- The baby has learnt to be pleased at the sound of its mother’s voice

There are several principles of classical conditioning:

  • Generalisation- When stimuli similar to the original CS (e.g. a bell with a different pitch) produce the CR (e.g salivating)

  • Discrimination- When stimuli similar to the original CS don’t produce the CR. This can be achieved by withholding the UCS (e.g. food) when a similar stimulus is used

  • Extinction- When the CR (e.g. salivating) isn’t produced as a result of the CS (e.g. bell). This happens when the CS is repeatedly presented without the UCS (e.g. food) following it

  • Spontaneous recovery- When a previously extinct CR is produced in response to the CS. This happens when the CS is presented again after some time during which it’s not been used

  • Higher order conditioning- When a new CS (e.g. a light) produces the CR because the animal associates it with the original CS. This can be achieved by consistently presenting the new CS before the original CS