Generalization during acquisition, extinction, and transfer of matching with an adjustable comparison.
Solid matching-to-sample training lets new stimuli work without extra drills.
01Research in Context
What this study did
Cohen (1969) worked with three pigeons in a small lab chamber.
The birds had to peck a center key that showed a color or line tilt.
Next they could peck a side key that let them adjust the comparison until it matched the sample.
The team tested if the birds would still match when brand-new colors and tilts appeared.
What they found
All pigeons learned to move the comparison key until it matched the sample.
When new samples popped up, accuracy stayed high.
The birds did not mix up the comparisons; they still picked the correct match.
Generalization happened without extra training on every single stimulus.
How this fits with other research
Bailey (1984) later showed the same pattern in preschool kids and adults.
Children who learned stable “sample-coding” gestures generalized matching right away.
Howard (1979) went further, proving pigeons could also transfer to symbolic matching after ordinary color training.
Together the three studies build a bridge: first pigeons, then people, then more abstract rules.
Why it matters
You do not need to teach every flashcard. Train a solid matching set with clear responses, then rotate in new pictures, fonts, or objects. The skill will carry over, saving you hours of trial time and keeping learners engaged with fresh material.
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02At a glance
03Original abstract
Three groups of pigeons were given conditional discrimination training in which the number of standard stimuli was varied across groups. In the presence of each standard, a pigeon adjusted the comparison stimulus on a second key until the two keys matched. A report of this match (response on the first key) was reinforced. Transfer of the matching performance was investigated by adding new standards to the ones already available. All pigeons were exposed to two extinction sessions after 155 sessions of training. Rapidity of acquisition was inversely related to the number of standards presented. Generalization gradients derived from the several comparison stimuli showed that all pigeons reached a high level of accuracy in the presence of at least one standard, and some pigeons did so in the presence of as many as four of the six standards. There was no evidence of a systematic effect of extinction upon overall accuracy, or the individual generalization gradients. When a new standard was added, a given pigeon's performance (in terms of responding to the comparisons) was similar to performance in the presence of one of the old standards. However, the pigeons did not show evidence of confusion among the comparisons.
Journal of the experimental analysis of behavior, 1969 · doi:10.1901/jeab.1969.12-463