Local response-rate constancy on concurrent variable-interval schedules of reinforcement

Area of Science:

• Behavioral psychology
• Operant conditioning

Background:

• Concurrent variable-interval (VI) schedules are used to study choice behavior.
• Matching law describes response allocation between concurrent schedules.
• Changeover mechanisms influence response patterns.

Purpose of the Study:

• Investigate matching behavior in pigeons under concurrent VI schedules.
• Examine the effects of different changeover procedures on response allocation and rates.
• Analyze local response rates and interresponse times in relation to schedule parameters.

Main Methods:

• Concurrent schedules with alternating main key colors and VI assignments were used.
• A changeover key required a small fixed ratio (FR) for response switching.
• Experiment 1: Assessed matching and local rates with unequal VI schedules.
• Experiment 2: Compared changeover delay (COD) with FR changeover procedures.

Main Results:

• Pigeons showed acceptable matching but a tendency toward overmatching in Experiment 1.
• Local response rates were higher for VI schedules with shorter interreinforcement intervals.
• Response output on the main key was greater with COD than with FR changeover.
• A 2-second COD increased response rate for 3 seconds post-changeover, unlike FR.

Conclusions:

• Concurrent VI schedules can produce matching, though overmatching may occur.
• Changeover procedures significantly impact response allocation and local response rates.
• Changeover delays appear more effective than fixed ratios in maintaining response output.