Vicarious conditioned acceleration: successful observational learning of an aversive Pavlovian stimulus contingency.
Rats can learn fear responses just by watching another rat experience shock — no direct aversive experience needed.
01Research in Context
What this study did
The team placed one rat in a clear box. A light came on, then the rat got a mild foot-shock.
A second rat watched from a nearby cage. It never felt the shock itself.
The scientists then tested the watcher rat alone. They turned on the same light and counted how fast the rat pressed a lever to avoid shock.
What they found
The watcher rat pressed faster after seeing the light-shock pairings. It learned the danger signal without being hurt.
When the model rat stopped getting shocked, the watcher’s lever pressing slowed. When shocks resumed, pressing sped up again.
The effect reversed and recovered, showing true observational learning, not just general fear.
How this fits with other research
Shimp et al. (1971) showed rats work hard to get a warning signal. Byrd (1972) adds that rats can learn that warning just by watching.
Mello (1966) proved punishment needs discrimination training to come under stimulus control. D’s observers gained that control without any direct training, extending the idea.
Fontes et al. (2018) used the same foot-shock tool but studied resurgence. D flips the focus: shock is not only something to escape; it is also information that can be shared socially.
Why it matters
Your clients may pick up fear or avoidance just by seeing peers face aversive events. Check what models are present during therapy. If one child gets a reprimand, watchers might learn to avoid the task even though they were never scolded. Use modeling videos or peer heroes to teach safe responses instead.
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02At a glance
03Original abstract
Five rats (observers) were trained to avoid unsignalled shocks in a shuttlebox and then habituated to brief light presentations. They were next confined on an observation platform while another rat (model) received light-shock pairings in the opposite compartment. The observers were exposed only to the sight and sound of the model during classical conditioning and were not shocked themselves. Test presentations of the light during subsequent avoidance sessions produced response rate increases (vicarious conditioned acceleration) comparable to those obtained in other studies where the avoidance animals were used in classical conditioning. Following sessions in which the model was not shocked after the light, the light presentations during avoidance eventually failed to elicit any response increases in the observers. When the model was again shocked, immediate recovery of avoidance acceleration occurred in the observers during the light.
Journal of the experimental analysis of behavior, 1972 · doi:10.1901/jeab.1972.18-181