Book Definition:The tendency to respond differently to two or more similar stimuli. In classical conditioning, it occurs when a stimulus similar to the conditioned stimulus fails to evoke the conditioned response; in operant conditioning, it occurs when an organism learns to make a response in the presence of other, similar stimuli that differ from it on some dimension.

In Your Own Words

  • Stimulus discrimination is when you react differently to two or more stimuli that are the same or similar. Such as different groups of friends or different adults.
  • Stimulus discrimination is very alike to stimulus generalization, yet is separating two stimuli instead of grouping them together.
  • Stimulus discrimination is when a conditioned stimulus is generalized with something similar sounding or looking.
  • When two stimuli that are similar are grouped together and cause the same reaction.
  • Often two stimuli, one conditioned stimulus and one similar to it, cannot be told apart or discriminated thus causing the response.


  • If you were to tell an inappropriate joke to a group of friends they might all laugh and find it funny. But if you were to tell the same joke to a group of teachers, they would probably not laugh and you would get in trouble. Both are groups of people, but you react to the similar stimulus with a different reaction.
  • Little Albert would generalize the fear of the white rat to some other white objects, while not being afraid of other white objects. The fear of only a few of the white things is stimulus discrimination.
  • Researcher Shenger-Krestovnika tested on dogs, the experiment was set up much like Pavolv's. He trained the dogs to salivate at the sight of a circe by pairing the sight with the taste of meat. After they were conditioned, the dogs salivated to the sight of things that looked like a circle such as ellipse.
  • If a bell is paired with salivation in dogs, after the bell noise has been conditioned the dogs may salivate to sounds similar to a bell.
  • This doesn't normally occur with experiments involving taste, since most foods do not taste similar.
external image Little-albert.jpg
Exhibit 1: Little Albert also became of anything white, not just white rats.

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