Task specificity in nonspecific transfer and in extradimensional stimulus generalization in pigeons.

Determined whether discrimination training per se is sufficient to produce positive nonspecific transfer and whether it sharpens extradimensional stimulus-generalization gradients, using domestic pigeons. In Exp I, 8 groups of Ss received true-discrimination (TD) or pseudodiscrimination training between 2 line orientations in either (a) a successive-conditional (SC) discrimination prior to transfer to a true SC or (b) a go/no go (GN) discrimination between 2 colors. Discriminative performance in transfer was facilitated only when the original and transfer discriminations were of the same type. Exp II showed that positive nonspecific transfer was primarily mediated by the transfer of task-specific learning rather than by the transfer of attentiveness. In Exp III, 4 groups were trained as in Stage 1 of Exps I and II and given single-stimulus training with a chromatic stimulus, followed by a wavelength stimulus generalization test. Only TD-GN discrimination training produced sharp gradients, an effect leading to the conclusion that GN discrimination training and stimulus generalization are closely related by task requirements rather than by attention. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)