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Determiners of selective stimulus control in the pigeon.

1970; American Psychological Association; Volume: 70; Issue: 2, Pt.1 Linguagem: Inglês

10.1037/h0020524

0021-9940

Daniel F. Johnson,

Animal Nutrition and Physiology

Twenty-two groups of pigeons were exposed to three experimental phases: single-stimulus discrimination training (SSDT), compound-stimulus discrimination (CSDT), and two-dimensional generalization test. The SSDT stimuli were vertical (SD) and horizontal (SA) white lines; in CSDT the lines appeared on chromatic backgrounds of 510 and 551 nm., respectively. In generalizatio n tests, 25 combinations of five line orientations and five background wavelengths were presented. The design examined the effects of (a) sequence of exposure to SSDT and CSDT, (b) intensity of lines in SSDT, and (c) duration of SSDT. Results indicated that control by the two stimulus dimensions was negatively correlated, and, in general, as SSDT line intensity and SSDT duration increased, line orientation control increased and background wavelength control decreased, regardless of SSDT-CSDT sequence. Findings suggested the operation of conditional dimension-specific mediating responses. Of four multidimensional generalization combination rules considered, a multiplicative rule best predicted test responding. Many observations indicate that simple discrimination training with compound stimuli does not guarantee that stimulus control will be exercised by all aspects of the stimulus compounds. Two experiments are now cla'ssic. Lashley (1938) found that rats trained to jump to stimulus cards containing a form were selec