What term describes a schedule of reinforcement in which a specific interval of time must elapse before the response yields reinforcement?

• A. Fixed-Interval Schedule
• B. Variable-Interval Schedule
• C. Fixed-Ratio Schedule
• D. Variable-Ratio Schedule

Answer: (A)

This is about reinforcement schedules that depend on time rather than the number of responses. In a fixed-interval schedule, reinforcement is provided for the first response after a fixed amount of time has passed since the last reinforcement. So if the interval is set at a specific duration, once that exact time elapses, the next correct response yields a reward, and the timer resets.

A useful way to picture it is to imagine timer-driven reinforcement: after the reward is earned, the clock starts again, and only after the fixed interval has elapsed will the next response be reinforced. This creates a characteristic pattern where responses tend to increase as the end of the interval approaches, then pause briefly right after reinforcement, then rise again as the next interval nears its end.

This differs from a variable-interval schedule, where the time until reinforcement varies unpredictably, producing a steadier, more consistent rate of responding. It also differs from fixed-ratio and variable-ratio schedules, where reinforcement depends on a certain number of responses, not on elapsed time.

So the term describing a schedule where a specific interval of time must pass before the response yields reinforcement is a fixed-interval schedule.