SPATIAL PEAK SHIFT AND GENERALIZATION IN PIGEONS

How pigeons generalize across spatial locations was examined in the 4 experiments reported in this article. During training, a square was pr esented at a fixed height at 1 of 2 horizontal locations on a monitor screen. One location (S+) signaled reward, whereas the other one (S-) signaled no reward. The birds were then tested occasionally with a ran ge of locations. After training with S+ only, the generalization gradi ent peaked at Sf and was approximately Gaussian in shape. After traini ng with equal numbers of S+ and S- trials, response rates were higher on the S+ side of the distribution. This asymmetry diminished over tes ting. When the S+ and S- were close together, the peak of responding w as shifted on initial generalization tests. Generalization gradients a long the orthogonal vertical dimension were approximately exponential in shape. This is the first demonstration of generalization and peak s hift in the spatial domain.