Classical Conditioning

A procedure in which a neutral stimulus (the conditioned stimulus or CS) is presented, followed by the presentation of a second stimulus (the unconditioned stimulus or UCS) that elicits a reflexive response (the unconditioned response or UCR) until the CS alone comes to elicit that reflexive response (the conditioned response or CR).The word "conditioned" may be thought of as meaning "learned":

• The conditioned stimulus (CS) is the learned stimulus — the stimulus that the organism will learn to respond to reflexively.The conditioned response (CR) is the learned response — the reflexive response to the CS that the organism will learn.The unconditioned stimulus (UCS) is the unlearned stimulus — the stimulus that the organism already responds to reflexively.
• The unconditioned response (UCR) is the unlearned response — the reflexive response to the UCS that the organism already expresses.

See: associative learning
See: instrumental learning
See: latent learning
See: observational learning
See: operant conditioning
See: vicarious conditioning