ABA Fundamentals

PARAMETERS AFFECTING THE ACQUISITION OF SIDMAN AVOIDANCE.

BOLLES et al. (1964) · Journal of the experimental analysis of behavior 1964
★ The Verdict

Immediate stimulus feedback, not just shock delay, drives rapid Sidman avoidance learning.

✓ Read this if BCBAs teaching safety skills or escape responses to learners with developmental disabilities.
✗ Skip if Clinicians focused only on purely appetitive reinforcement without avoidance components.

01Research in Context

01

What this study did

Researchers ran four small experiments with rats. They wanted to know what makes Sidman avoidance click. They varied how quickly the cage light changed after a lever press. They also varied how long each shock-free period lasted.

The team kept the shock schedule the same: every 20 s unless the rat pressed. Only the feedback signals moved.

02

What they found

Rats learned fastest when the cage light flipped the instant they pressed. A short, bright cue beat a long, dim one. Shock postponement alone was not enough. The immediate stimulus change did the teaching.

Once the light followed the response by even half a second, learning slowed.

03

How this fits with other research

Thomas et al. (1968) later showed the flip side. When they removed shocks entirely, avoidance crashed in under four hours. Together the two papers paint a full picture: quick feedback builds the response; removing the aversive contingency tears it down.

Leander et al. (1972) extended the idea. They used a shuttlebox and hit 70 % avoidance in the first session. Their rapid method built on the same instant-feedback rule BOLLEHOFFMAN et al. (1964) identified.

ANGER (1963) had already guessed why the cue matters. He argued rats time the gap between response and shock. The shorter that gap feels, the safer the rat rates the situation. C et al. gave the hard data that backed his temporal-discrimination story.

04

Why it matters

When you shape escape or avoidance in any species, deliver the safety signal right away. A half-second delay can double training time. Use a bright, brief cue that clearly marks the new shock-free period. Pair that cue with your differential reinforcement of other behavior to speed acquisition and later extinction if needed.

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→ Action — try this Monday

Program your safety-skill protocol so the praise or light change occurs within 0.5 s of the correct response.

02At a glance

Intervention
other
Design
single case other
Population
not specified
Finding
positive

03Original abstract

Four studies were conducted to investigate the source of reinforcement of Sidman avoidance. First it was found that the acquisition of avoidance was seriously impaired if there was no immediate stimulus consequence of responding, i.e., proprioceptive and auditory feedback. The second study showed that if the shock-shock interval was split so that only responses occurring in one half of the interval were effective in postponing shock, then learning was impaired. It made little difference which half of the interval was used. The third study demonstrated that Ss learn Sidman avoidance more quickly with a variable shock-shock interval than with the usual fixed-interval procedure. The results of the second and third experiments argue against the view that avoidance is reinforced by the decrease in conditioned aversiveness that occurs at long post-shock times. The final experiment indicated that Ss do not learn Sidman avoidance if the response-produced delay of shock is preceded by a shock, hence it seems unlikely that the crucial source of reinforcement is merely an overall reduction in shock density. All of the findings are consistent with the hypothesis that the avoidance response is reinforced by the decrease in conditioned aversiveness of stimuli at short post-response times. This seems to be the case even at the beginning of acquisition.

Journal of the experimental analysis of behavior, 1964 · doi:10.1901/jeab.1964.7-315