| Abstract: | In three experiments, groups of pigeons were tested for wavelength generalization of auto-shaped key-pecking following different types of training. In Experiment I, one group received auto-shape trials with a 555-nm CS. Another group received auto-shape trials with a 555-nm CS and a white CS. A third group received auto-shape trials with a 555-nm CS and a white CS, except the white CS was nonreinforced. The third group yielded the sharpest gradient, whereas the second group yielded the flattest gradient. In Experiment II, one group received auto-shape trials with a 555-nm CS. A second group received auto-shape trials with a 555-nm CS and a compound CS consisting of a vertical white line on a 555-nm background. A third group received auto-shape trials with a 555-nm CS and a compound CS, except that the compound was nonreinforced. The third group yielded the sharpest wavelength gradient, whereas the second group yielded the flattest. In Experiment III, exposure differences to 555 nm in Experiment II resulting from differential speeds of auto-shape acquisition were controlled by the use of an ITI manipulation. Amount of exposure to 555 nm was shown not to be responsible for the results of Experiment II. |
