Contextual control of discriminated operant behavior.

Area of Science:

• Behavioral neuroscience
• Learning and memory
• Animal behavior

Background:

• Contextual changes after instrumental conditioning can weaken operant responses.
• This contrasts with Pavlovian conditioning, where context switches often do not affect conditioned responses.

Purpose of the Study:

• To investigate the role of context switching in operant conditioning in rats.
• To compare the effects of context change in operant conditioning with findings in Pavlovian conditioning.

Main Methods:

• Rats were trained on a discriminated operant response (lever pressing or chain pulling) reinforced by a specific stimulus (tone or light) in Context A.
• Subsequent testing occurred in a different context (Context B) to assess the impact of the context switch on the operant response.
• Various control conditions were used to equate familiarity and associations of Context B with reinforcement and other operant tasks.

Main Results:

• A context switch from A to B decreased responding during the discriminative stimulus (S).
• This decrement occurred even when the new context was equally familiar or associated with reinforcement or other tasks.
• No decrement was observed if the new context was previously associated with the same operant response trained in Context A.
• The discriminative stimulus remained effective across contexts, but response strength did not transfer.
• A continuously reinforced response was also disrupted by context change when the same manipulandum was used.

Conclusions:

• Context plays a significant and general role in controlling operant behavior.
• The findings suggest that the strength of an operant response is not solely dependent on the discriminative stimulus but is also modulated by contextual cues.
• Mechanisms underlying contextual control in operant conditioning warrant further investigation.