ABA Fundamentals

Rules: Function-altering contingency-specifying stimuli.

Blakely et al. (1987) · The Behavior analyst 1987
★ The Verdict

Rules are function-altering stimuli that create new contingencies, not simple cues.

✓ Read this if BCBAs who write behavior contracts or teach self-management.
✗ Skip if Clinicians working only with non-verbal populations who rely on immediate cues.

01Research in Context

01

What this study did

The authors looked at how spoken or written rules control behavior.

They asked: is a rule just a cue that says "do this now," or something more?

Using logical analysis, they argued rules are special stimuli that change how other stimuli work.

They coined the term "function-altering contingency-specifying stimuli" to replace the old label "discriminative stimulus."

02

What they found

Rules don’t simply tell a person what to do next.

Instead, they create new contingencies that can affect behavior hours or days later.

Calling rules "discriminative stimuli" misses this long-term, contingency-building power.

03

How this fits with other research

Sherwell et al. (2014) showed that brief added cues help animals tell when reinforcer ratios will flip.

Their data support the idea that stimuli can specify upcoming contingencies, matching E et al.’s view.

Fields et al. (2018) go further, showing that meaningful stimuli speed up equivalence class formation.

Both papers agree that a stimulus can alter stimulus functions, backing the function-altering claim.

Catania (2021) adds that contingencies define operant classes trial-by-trial, not single responses.

Together, these studies say: contingencies are specified by stimuli, and those stimuli can re-wire behavior.

04

Why it matters

When you write a behavior plan, think of your written rule as a tool that builds future contingencies, not just a prompt.

State the rule clearly, then let natural delays test its power.

If the learner follows hours later, your rule worked as a function-altering stimulus.

Track those delayed effects to see if the contingency you specified actually took hold.

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→ Action — try this Monday

Write one clear rule in the behavior plan, then check if the client follows it after a delay of at least 30 minutes.

02At a glance

Intervention
not applicable
Design
theoretical
Finding
not reported

03Original abstract

Behavior analysts have traditionally defined rules as discriminative stimuli. Three problems with this interpretation are discussed. First, because the effects of rules are often delayed, and the effects of discriminative stimuli are immediate, classifying rules as discriminative stimuli violates the definitional requirements of the latter. Second, when rules are defined as discriminative stimuli, other truly unique effects of rules may be obscured. Finally, both rules and contingencies develop new behavioral relations; however, when rules are interpreted as discriminative stimuli, their effects are not readily compared with those of contingencies. As an alternative, we suggest that rules be interpreted as function-altering contingency-specifying stimuli. Implications of this function-altering interpretation for terminology and research strategy are discussed.

The Behavior analyst, 1987 · doi:10.1007/BF03392428