ABA Fundamentals

Timing the second response in two-response avoidance.

Fairhurst et al. (1983) · Journal of the experimental analysis of behavior 1983
★ The Verdict

Avoidance response latency scales one-to-one with the safe-time window you set.

✓ Read this if BCBAs teaching safety or self-help chains in clinics or schools.
✗ Skip if Clinicians working only with vocal manding or token boards.

01Research in Context

01

What this study did

Researchers watched rats press a lever to avoid shock.

They changed how long the rat had to press before the next shock.

They measured how long the rat waited before pressing again.

02

What they found

The rats waited longer when the safe window was longer.

The wait time grew in a straight line with the safe time.

This fits scalar timing: the rat keeps track of time like a stopwatch.

03

How this fits with other research

Corrigan et al. (1998) later showed the same rule works with people.

Adults breathed to avoid short CO2 puffs.

Their breathing timing followed the same straight-line rule, so the rat law crosses species.

Parsons et al. (1981) had already shown rats do more than lever-press when scared; they also bury.

That study helps us see the lever-press timing is special, not just general fear.

04

Why it matters

You can predict when a learner will make the next safety response if you know the safe window you gave them.

Set a 10-second window? Expect the response around 9 seconds.

Use this to spot timing problems in self-protection skills or over-repeated prompts.

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→ Action — try this Monday

Start your next safety drill and count the seconds between the cue and the learner’s move; compare it to the window you set.

02At a glance

Intervention
not applicable
Design
other
Population
not specified
Finding
not reported

03Original abstract

Rats were trained on a free-operant avoidance task requiring two lever presses within R seconds, with the opportunity for each response distinguished by differing stimuli. Response latencies at a variety of response-shock intervals were found to be proportional to the time available for the response. These results are shown to be consonant with a scalar expectancy model of timing behavior.

Journal of the experimental analysis of behavior, 1983 · doi:10.1901/jeab.1983.39-199