How does a fixed interval schedule work?

A fixed interval schedule is a reinforcement schedule in which a reward is presented following the first instance of a desired behavior after a predetermined amount of time has passed. This means that the behavior must occur only after the specified time has elapsed to receive reinforcement.

For instance, if a person is rewarded for completing a task every 10 minutes, they will only receive the reward after the 10-minute period has passed and the task is completed. This leads to a pattern where the frequency of the desired behavior may increase as the reinforcement time approaches, but there may be fewer responses immediately after receiving the reward.

This understanding is fundamental in behavioral psychology, as it distinguishes this schedule from other types, such as variable interval schedules where the timings for reinforcement vary, or continuous reinforcement where every instance of the behavior is rewarded.