Conditioned Response

In classical conditioning, a conditioned response is a behavior that is learned in response to having been repeatedly paired over time with a specific stimulus.

Reflexive behaviors occur when an animal encounters a stimulus that naturally leads to a reflex. For example, an unexpected loud noise generates a startle response. If an initially neutral stimulus is paired with the noise, that neutral or conditioned stimulus will eventually produce a startle response. In classical conditioning, the response to the conditioned stimulus is called a conditioned response.

Conditioned responses develop in a process called acquisition, in which the natural or unconditioned stimulus is repeatedly paired with the conditioned stimulus. Some responses develop more quickly than others, and some responses are stronger than others. The nature of the conditioned response depends on the circumstances in which acquisition occurs. The conditioned response emerges most effectively if the conditioned stimulus appears slightly before the unconditioned stimulus. This process is called delayed conditioning, because the unconditioned stimulus is delayed relative to the conditioned stimulus. The response is weaker if the conditioned and unconditioned stimuli begin simultaneously, and it becomes progressively weaker the more the unconditioned stimulus precedes the conditioned stimulus. In general, the conditioned response resembles the unconditioned response (e.g., the normal startle response) closely. Research psychologists have shown that the conditioned response is not precisely identical to the unconditioned response and may be quite substantially different.

An animal frequently produces conditioned responses to stimuli resembling the conditioned stimulus, a process called stimulus generalization. Balancing this is a complementary tendency not to respond to anything but the conditioned stimulus itself; this is called stimulus discrimination. The combination of generalization and discrimination leads to the generation of desired responses.

See also Classical conditioning ; Conditioned stimulus ; Conditioning ; Counterconditioning ; Operant conditioning .



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