ABA Fundamentals

Effects Of Fixed-interval Schedule And Reinforcer Duration On Responding Reinforced By The Opportunity To Run.

Belke et al. (1998) · Journal of the experimental analysis of behavior 1998
★ The Verdict

Short activity breaks keep clients working; long ones create long pauses.

✓ Read this if BCBAs using movement, screen, or toy access as reinforcement.
✗ Skip if Clinicians who only use edible or token reinforcers.

01Research in Context

01

What this study did

Scientists let rats press a lever to earn wheel-running time.

They used fixed-interval schedules: the first press after a set time produced the reinforcer.

Run time varied from 30 seconds to four minutes.

Schedule length varied from 30 to 300 seconds.

The team counted lever presses, pauses, and wheel turns.

02

What they found

Longer wheel time cut later lever pressing.

Longer FI values raised overall response rate.

Post-reinforcement pause stayed long no matter the schedule.

Running itself did not change much across conditions.

03

How this fits with other research

Foltin (1997) saw the same drop a year earlier.

That paper used almost the same set-up, so the effect is solid.

Staddon (1970) found the same pause pattern with milk instead of running.

Oliver et al. (2002) later showed the pause also appears in children learning to talk.

Across species and reinforcers, bigger or longer rewards stretch the pause.

04

Why it matters

When you use activity reinforcers, keep access short.

Thirty seconds of iPad or playground may maintain work better than five minutes.

Watch the post-reinforcement pause; it can eat session time.

Pick schedule length for rate goals, but pick reinforcer length for pause control.

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→ Action — try this Monday

Cut your current activity reinforcer to 30 s and track response rate.

02At a glance

Intervention
other
Design
single case other
Sample size
16
Population
neurotypical
Finding
not reported

03Original abstract

Two experiments investigated the effects of schedule value and reinforcer duration on responding for the opportunity to run on fixed‐interval (FI) schedules in rats. In the first experiment, 8 male Wistar rats were exposed to FI 15‐s, 30‐s, and 60‐s schedules of wheel‐running reinforcement. The operant was lever pressing, and the consequence was the opportunity to run for 60 s. In the second experiment, 8 male Long‐Evans rats were exposed to reinforcer durations of 15 s, 30 s, and 90 s. The schedule of reinforcement was an FI 60‐s schedule. Results showed that postreinforcement pause and wheel‐running rates varied systematically with reinforcer duration but not schedule value. Local lever‐pressing rates decreased with reinforcer duration. Overall lever‐pressing rates decreased with reinforcer duration but increased with schedule value. Although the reinforcer‐duration effect is consistent with previous research, the lack a schedule effect appears to be the result of long post‐reinforcement pauses following wheel‐running reinforcement that render the manipulation of the interval requirement ineffective.

Journal of the experimental analysis of behavior, 1998 · doi:10.1901/jeab.1998.70-69