The effects of reinforcement upon the prepecking behaviors of pigeons in the autoshaping experiment.
Reinforcement grows the tiny orienting moves that grow into the final response.
01Research in Context
What this study did
Semb (1974) watched pigeons during an autoshaping procedure. The team tracked every tiny head turn and step toward the key before any peck happened.
They wanted to see if food delivery could strengthen these early, pre-peck movements.
What they found
Reinforcement did not just create the final key peck. It built the baby steps—orientation and approach—that came first.
The peck emerged piece by piece, each small move made stronger by grain.
How this fits with other research
Handleman et al. (1980) later added an auditory cue and got second-order autoshaped pecking. Their extra layer shows the same shaping rules still apply when the reinforcer is one step removed.
Hursh et al. (1974) looks like a clash—same year, same species, yet automaintenance failed for most birds. The difference is what kept the response alive: G's birds got food after the stimulus; R's birds only got stimulus change. Food won, light offset did not.
Rasing et al. (1992) extended the idea into peak-shift. Once the basic peck was shaped, they showed autoshaped birds give even bigger generalization shifts than operant birds, proving the early shaping holds up in new tests.
Why it matters
When you shape any new skill, reinforce the mini-steps that come before the target response. A child may not yet touch the picture card, but looking at it or leaning forward is your starting behavior. Capture and reinforce those small orientations just like G's grain strengthened the pigeon's head turns. The final response will follow the same brick-by-brick path.
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02At a glance
03Original abstract
The autoshaping procedure confounds the effects of pairing a keylight and food with the effect of adventitious food reinforcement of responses that typically occur before the pecking response. In Experiment I, acquisition of the orientation to the key, the approach toward the key, and the peck at the key were systematically monitored. Orientations to the key and approaches toward the key frequently occurred in contiguity with food presentation before peck acquisition. In Experiment II, a negative contingency procedure was used to assess the sensitivity of the approach toward the key to its consequences. When the approach toward the key resulted in nonreinforcement, the probability of occurrence of that response decreased to zero despite repeated light-food pairings. In Experiment III, peck probability was shown to be determined during the approach toward the key by the presence of stimuli that had previously been either paired or nonpaired with food. In Experiment IV, it was shown that the effects of the stimulus present during the approach toward the key were not due solely to the effects of pairing that stimulus with food. Autoshaped key pecking appears to be determined by the interacting effects of stimulus-reinforcer and response-reinforcer variables upon orientations to, approaches toward, and pecks at the lighted key.
Journal of the experimental analysis of behavior, 1974 · doi:10.1901/jeab.1974.21-125