Classical Conditioning

Stimulus

Unconditioned stimulus (US) = stimulus produces a natural or instinctual reaction without any kind of “training” or “teaching”.

  • Unconditioned stimulus (US) elicits an unconditioned response (UR)

Some examples:

  • the food (US) automatically makes the dog drool (UR)
  • loud noises (US) that startle us (UR)
  • hot shower (US) that produces pleasure (UR)

Conditioned Stimulus (CS) = initially neutral stimulus (like a bell, light, or tone) that elicits a conditioned response after it has been associated with an unconditioned stimulus

  • Conditioned Stimulus (CS) produces a conditioned response (CR)

Examples:

  • the bell sound (CS) automatically makes the dog drool (UR) in Palvov’s experiment
  • seeing the restaurant’s logo (CS) triggers a hunger feeling (CR).

In this example,

  • The dog food is an unconditioned stimulus (US) because it elicits an unconditioned response (UR)