A neutral stimulus is something that, at first, does not cause any specific automatic response or emotion in an organism.

Simple definition

In psychology, especially in classical conditioning , a neutral stimulus (NS) is:

  • A sound, image, smell, object, or event that initially has no particular meaning or emotional effect for the person or animal.
  • It draws attention at most, but it does not trigger the reflex or behavior the researcher is interested in.

Example:
A bell that rings in a room where a dog is just relaxing is a neutral stimulus if the bell does not make the dog salivate or react in any special way.

How it works in conditioning

In classical conditioning:

  1. You start with:
    • Neutral stimulus (NS): e.g., a bell sound.
 * Unconditioned stimulus (US): e.g., food that naturally makes the dog salivate.
  1. You repeatedly pair NS + US together (bell then food).
  1. Over time, the previous neutral stimulus becomes a conditioned stimulus (CS) that now does trigger salivation on its own.

So, the neutral stimulus is essentially the “before learning” version of what can later become a conditioned stimulus.

Quick fact bullets

  • A neutral stimulus has no built‑in meaning for the response being studied.
  • Almost any stimulus can be neutral at first, depending on the context and what response you care about.
  • Once it reliably triggers a learned response, it stops being “neutral” and is called a conditioned stimulus.

Bottom note: Information gathered from public forums or data available on the internet and portrayed here.