ABA Fundamentals

Stimulus control of respondent and operant key pecking: A single key procedure.

Marcucella (1981) · Journal of the experimental analysis of behavior 1981
★ The Verdict

Brief signals that predict free treats can trigger automatic, reflex-like responses separate from deliberate operant pecks.

✓ Read this if BCBAs who need to tell respondent bursts from operant acts in early learners.
✗ Skip if Clinicians working only with verbal adults where reflexive behavior is rare.

01Research in Context

01

What this study did

Tager-Flusberg (1981) worked with pigeons in a small lab cage.

One key sat in the middle of the front wall.

Short red or green lights came on for two seconds.

Red meant grain would follow no matter what.

Green meant no grain would come.

The bird could peck the key or just wait.

The team counted every peck and timed each one.

02

What they found

When the red light blinked on, birds pecked fast and hard.

These pecks looked stiff and automatic.

When the green light blinked on, most birds froze.

A few still pecked, but slowly and softly.

The quick red-light pecks came before any grain showed up.

This showed two kinds of control: a reflex-like burst and slower choice pecks.

03

How this fits with other research

Ramer et al. (1977) saw the same birds mix two controls.

They found that if the stimulus-reinforcer link was weak, response-reinforcer links took over.

Tager-Flusberg (1981) tightened the design and split the two kinds of pecks apart.

Paul (1983) later showed that even ratio numbers can act like colored lights.

Together the three papers map how stimuli can steer behavior with or without extra work requirements.

04

Why it matters

You can test whether a client’s behavior is a reflex cued by signals or an operant kept by pay-offs.

First, show a brief picture or sound that has always meant a treat is coming no matter what the child does.

Count immediate reactions in the first two seconds.

If you see quick, rigid responses, you may be looking at respondent control.

Next, require a specific action for the same treat.

Slower, flexible responding will point to operant control.

Use this split to pick the best intervention: stimulus fading for reflexive bursts or reinforcement thinning for operant chains.

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Flash a picture that has always meant a free item; count any immediate stereotypic responses in the first two seconds to spot respondent control.

02At a glance

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

03Original abstract

Pigeons' responses to a uniformly illuminated response key were either reinforced on a variable-interval one-minute schedule of reinforcement or extinguished for one-minute periods. When 1.5 second signals were presented at the beginning of each component, so as to differentially predict reinforcement, the pigeons pecked at the signals, at rates higher than rates during the remainder of the component. When the brief signals were not differentially predictive of reinforcement, pecking in their presence decreased to near zero levels. Similar results were obtained with signals based upon colors and upon line orientations. Changes in rates of (unreinforced) pecking occurred during the signal whether pigeons responded differentially during the remainder of the component or not. Experiment II demonstrated that the presence of the signal correlated with extinction was not necessary for pecking to develop at the signal which preceded the component in which responding was intermittently reinforced. The experiments demonstrated a clear dissociation of respondent control from operant control of a response. In addition, operant behavior was shown to be relatively insensitive to differing rates of reinforcement, as compared to the sensitivity of respondent behavior to differing rates of reinforcement produced by the very same operant behavior.

Journal of the experimental analysis of behavior, 1981 · doi:10.1901/jeab.1981.36-51