Conditioned acceleration and conditioned suppression in pigeons.
A stimulus can either suppress or accelerate behavior depending on what bad event it predicts.
01Research in Context
What this study did
Pigeons pecked a key for food. A light or tone came on before different bad events.
Sometimes the signal meant a quick shock. Sometimes it meant a short time-out from food. Other times it meant noise or just a tone.
What they found
Shock signals made the birds stop pecking. Time-out signals made the birds peck faster. Noise and tone signals did nothing.
Same birds, same key, same food. Only the promised consequence changed the response.
How this fits with other research
HAKMCMILLAN et al. (1965) and SHETTLEWORTCHARNEY et al. (1965) already showed that shock paired with a response cuts pecking. The 1966 study adds a twist: shock still suppresses if it is only signaled, not contingent.
Hake et al. (1967) later showed that stronger shock gives stronger suppression in monkeys. Rachlin (1966) matches that dose idea: shock signals suppress, but milder time-out signals do the opposite.
Dougan (1992) later proved pigeons will work to cancel a coming time-out. That supports the 1966 finding: birds treat time-out as aversive, so its signal speeds responding to grab food before the pause.
Why it matters
Your warning cues can either brake or gas the behavior that is already running. If the client fears a painful consequence, expect a freeze. If the client only faces a brief loss of reinforcers, expect a burst of quick responses to stock up. Check what your signal really promises before you use it in treatment.
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02At a glance
03Original abstract
Two experiments were performed to investigate the effects on pigeons' keypecking behavior of stimuli that signal different kinds of aversive events: time-out from positive reinforcement, electric shock, loud noise, and loud tone. Behavior maintained by a variable-interval schedule of reinforcement was suppressed by a stimulus before shock, was accelerated by a stimulus before time-out from positive reinforcement, and was unchanged by a stimulus before loud noise or a stimulus before loud tone. Conditioned acceleration with time-out from positive reinforcement and conditioned suppression with shock were obtained regardless of whether a response contingent or response-independent procedure was employed.
Journal of the experimental analysis of behavior, 1966 · doi:10.1901/jeab.1966.9-205