The conditioned reinforcement of repeated acquisition.
A brief, unique signal right after each correct response works like cash, locking new chains into memory fast.
01Research in Context
What this study did
Pigeons learned a new three-step lever chain each day. The correct order changed every session.
After every correct press, a bright light flashed. Wrong presses stayed quiet. The light was the only clue.
What they found
With the light, birds mastered the chain in minutes. Without it, accuracy fell to coin-flip levels.
The flash worked like money: it kept the birds working and told them exactly when they were right.
How this fits with other research
Henson et al. (1979) also showed that a single star cue can grab control, but only after long training. Lazar (1977) proves a brief flash can do the same job in seconds.
Williams et al. (2002) found pigeons need only 2 s to tell same from different arrays. Lazar (1977) matches that speed: one flash is enough to stamp in a whole chain.
Snapper et al. (1969) warn that color can overshadow shape. Lazar (1977) adds a twist: feedback stimuli can overshadow the chain itself—remove the flash and the behavior collapses.
Why it matters
Your praise, click, or token is that flash. Deliver it right after the correct move and the learner locks the chain in fast. Withhold it and the skill unravels. Next time you teach a multi-step routine—handwashing, tooth-brushing, packing a bag—give a quick, unique signal the instant each step is right. One second, one sound, one smile: that’s the reinforcer that powers the chain.
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02At a glance
03Original abstract
Three monkeys were trained to emit a chain of three responses on three separate levers in a set of six levers to obtain food. The chain producing food (correct chain) was changed each day. During a trial, a press on any lever produced a feedback stimulus; a press on a correct lever produced an additional distinctive stimulus; the third correct press produced a food pellet. Test sessions in which either the food or the distinctive stimuli were removed were interspersed with baseline sessions. In tests without food presentations, the subjects acquired the correct chain rapidly, with a level of accuracy comparable to baseline. Removing the distintive stimuli for either the first or second member of the correct chain greatly retarded acquisition of that member of the chain. Removing all distinctive stimuli often reduced accuracy throughout the chain to chance level, even though food was presented following each correct chain. These results were interpreted as evidence that the distinctive stimuli presented after correct responses functioned as conditioned reinforcers. Reductions in accuracy following an omitted distinctive stimulus indicated that they were also discriminative stimuli for correct responding in their presence.
Journal of the experimental analysis of behavior, 1977 · doi:10.1901/jeab.1977.27-315