Ensayo

J Exp Anal Behav. 1978 Sep;30(2):177-86.
Same/different concept learning in the pigeon: the effect of negative instances and prior adaptation to transfer stimuli.
Zentall TR, Hogan E.
AbstractPigeons were trained on a matching-to-sample or oddity-from-sample task with shapes (circle and plus). Half of each group was exposed to "negative instance" trials i.e., for matching birds, neithercomparison key matched the sample, and for oddity birds both comparison keys matched the sample. When all birds were transferred to a new task involving colors (red and green), nonshifted birds(transferred from matching to matching, or oddity to oddity) performed significantly better than shifted birds (transferred from matching to oddity, or oddity to matching), but only if they had experiencednegative instances of the training concept. When all birds were exposed to negative instances of the transfer task and then transferred to a new color task (yellow and blue), dramatic transfer effectswere observed. The effect of pre-exposure to the yellow and blue colors, in order to reduce transfer-stimulus novelty, had a minor effect on transfer.

Journal of experimental psychology Animalbehavior processes (2003)
Volume: 29, Issue: 1, Pages: 84-91
* PubMed: 12561136
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Abstract
The authors taught pigeons to discriminate displays of 16identical items from displays of 16 nonidentical items. Unlike most same-different discrimination studies-where only stimulus relations could serve a discriminative function-both the identity of theitems and the relations among the items were discriminative features of the displays. The pigeons learned about both stimulus identity and stimulus relations when these 2 sources of information served asredundant, relevant cues. In tests of associative competition, identity cues exerted greater stimulus control than relational cues. These results suggest that the pigeon can respond to both...