Answer:
fixed interval reinforcement schedule
Explanation:
Fixed Interval Reinforcement Schedule is a form of reinforcement schedules where by behavior is rewarded or delivered after a set amount of time intervals. For example; 4, 8, 12, and 16 minutes
It is believed that, Fixed Interval Reinforcement Schedule causes high amounts of responding near the end of the interval but much slower responding immediately after the delivery of the reinforcer.
Hence, it was noticed that the pigeon seems to increase its rate of responding towards the end of a two minute period, food is made available, and then lever pressing slows until the end of the next two minutes.