ABA Fundamentals

Effects of differences in interreinforcer intervals between past and current schedules on fixed-interval responding.

Okouchi (2003) · Journal of the experimental analysis of behavior 2003
★ The Verdict

Old reinforcement pace silently sets the speed dial when clients move to fixed-interval work.

✓ Read this if BCBAs writing schedule thinning plans or shifting between DR and FI contingencies.
✗ Skip if Clinicians who only use continuous reinforcement and never change schedules.

01Research in Context

01

What this study did

Okouchi (2003) worked with pigeons on fixed-interval schedules.

First the birds lived under mixed fixed-ratio or DRL schedules.

Then the team switched them to a fixed-interval schedule and watched response speed.

02

What they found

Birds that came from fast ratio schedules kept pecking quickly on FI.

Birds that came from slow DRL schedules pecked more slowly.

The prior inter-reinforcement time acted like a hidden cue for current speed.

03

How this fits with other research

Hirai et al. (2011) later saw the same pattern with human button pressing, so the effect crosses species.

Okouchi et al. (2006) showed the cue is pure time, not just old response speed, tightening the 2003 story.

Ley (2001) looks like a contradiction: after 80-100 FI sessions, rat history effects vanished.

The gap is baseline length; short transitions keep the history, long exposure washes it out.

04

Why it matters

Your client’s past schedule matters when you change contingencies.

If a child just finished a dense DR, expect quicker responding on a new FI token board.

Start with short FI values and watch for carry-over; give more practice if the old pattern lingers.

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→ Action — try this Monday

Note the client’s last schedule; if it was fast, begin the new FI with extra prompts for slower, steady responding.

02At a glance

Intervention
other
Design
single case other
Population
neurotypical
Finding
positive

03Original abstract

Undergraduates were exposed to a mixed fixed-ratio differential-reinforcement-of-low-rate schedule. Values of the schedule components were adjusted so that interreinforcer intervals in one component were longer than those in another component. Following this, a mixed fixed-interval 5-s fixed-interval 20-s schedule (Experiment 1) or six fixed-interval schedules in which the values ranged from 5 to 40 s (Experiment 2) were in effect. In both experiments, response rates under the fixed-interval schedules were higher when the interreinforcer intervals approximated those produced under the fixed-ratio schedule, whereas the rates were lower when the interreinforcer intervals approximated those produced under the different-reinforcement-of-low-rate schedule. The present results demonstrate that the effects of behavioral history were under control of the interreinforcer intervals as discriminative stimuli.

Journal of the experimental analysis of behavior, 2003 · doi:10.1901/jeab.2003.79-49