ABA Fundamentals

Successive independence of multiple-schedule component performances.

McLean (1988) · Journal of the experimental analysis of behavior 1988
★ The Verdict

One schedule piece can stay calm while another shifts, if its cue never hints at the other’s pay.

✓ Read this if BCBAs who run multi-part sessions or alternate work and play.
✗ Skip if Clinicians who use only single, unchanging reinforcement all day.

01Research in Context

01

What this study did

McLean (1988) worked with pigeons in a two-part schedule.

One part always stayed the same. The other part changed how often food came.

The team watched if the steady part changed when the other part did.

02

What they found

The birds kept the same peck rate and time in the steady part.

Even when food odds changed next door, that corner stayed calm.

This shows parts of a schedule can act alone.

03

How this fits with other research

Dove (1976) saw the opposite. When one part paid more, birds pecked harder at the start of the next part.

The gap is in the cue line. D tied each color to its own pay rate. P kept one color blind to the other’s odds.

Last et al. (1984) adds that time inside a part also bends numbers. Put together, the three say: link the cue to the pay and you get cross-talk; keep the cue neutral and you get peace.

04

Why it matters

You can kill side-effects by unlinking the signal. In a split day of table work and break time, keep the break signal silent about the work pay. The child stays steady at the table no matter how rich the break bucket is.

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Keep your “work” SD blind to the “reinforcer room” odds—use a neutral card or word so the work rate never chases the prize rate.

02At a glance

Intervention
not applicable
Design
single case other
Population
not specified
Finding
not reported

03Original abstract

In three experiments, pigeons' responses were reinforced on two keys in each component of a series of multiple-schedule conditions. In each series, concurrent variable-interval schedules were constant in one component and were varied over conditions in the other component. In the first experiment both components arranged the same, constant total number of reinforcers, in the second the two components arranged constant but different totals, and in the third experiment the total was varied in one component and remained constant in the other. Relative reinforcer rate during the varied component was manipulated over conditions in all three experiments. In all these experiments, response and time allocation in the constant component were invariant when reinforcer ratios varied in the other component, demonstrating independence of behavior allocation in a multiple-schedule component from the relative reinforcer rate for the same alternatives in another component. In the two experiments which maintained constant reinforcer totals in components, sensitivity to reinforcement in the multiple schedules was the same as that in the concurrent schedules arranged during the varied component, with multiple-schedule bias in the experiment in which the totals were unequal.

Journal of the experimental analysis of behavior, 1988 · doi:10.1901/jeab.1988.49-117