| Abstract: | Three groups of 12 pigeons each were trained to discriminate between lights of 550 mμ (SD), correlated with 1-min variable-interval reinforcement and 570 mμ (SΔ), correlated with extinction. Group A was tested for wavelength generalization in extinction 1 min after meeting the discrimination criterion; Group B was tested 24 hr later; Group C was tested 24 hr later after a 3-min (reinforced) warm-up with the SD. The post-discrimination gradient of Group B was significantly flatter and showed significantly greater area shift than that of Groups A and C. The gradient of Group C was similar to that of Group A, indicating that the warm-up eliminated the effect of the delay period. |
