Which term describes the ability to distinguish between similar stimuli and respond only to the specific conditioned stimulus?

• A. Stimulus generalization
• B. Stimulus discrimination
• C. Extinction
• D. Habituation

Answer: (B)

Discrimination in classical conditioning is the ability to distinguish between similar stimuli and respond only to the specific conditioned stimulus. Through learning, an organism learns that only one exact cue predicts the unconditioned stimulus, while other close cues do not. This sharpens the response to the trained cue and reduces or eliminates responses to similar, non-predictive stimuli. For example, if a dog is conditioned to salivate to a exact-tone of a certain frequency, it will respond to that tone but not to tones that are only slightly different if those tones don’t signal the unconditioned stimulus.

If you hear the term generalization, that would mean the organism responds to a range of similar stimuli as if they all predict the unconditioned stimulus. Extinction refers to the decrease of the conditioned response when the conditioned stimulus is presented without the unconditioned stimulus. Habituation is a decrease in response to a repeated, harmless stimulus over time. The concept described here—learning to respond only to the precise conditioned stimulus—is discrimination.