Forgetting of visual discriminations by pigeons

Three experiments examined the forgetting of visual discriminations by 48 Silver King pigeons. The problems consisted of feature discriminations, with dot displays as the discriminative stimuli, and involved a successive go/no-go pecking response. In all 3 experiments, Ss trained to refrain from pecking an S- display resumed pecking at this display after retention intervals. It is argued that these data represent the 1st direct demonstration of forgetting of a discrimination by pigeons. Exp I also showed that the amount of forgetting progressively increased, in a negatively accelerated fashion, over intervals of 1, 10, and 20 days. Also, more S- responses occurred during relearning a reverse discrimination than after relearning a nonreverse discrimination. In Exp II, acquisition was retarded and more forgetting occurred for discriminations that involved more highly similar stimuli. In Exp III, a change in contextual cues between acquisition and retention testing enhanced forgetting when the contextual cues present during original acquisition were conspicuous; when these cues were relatively inconspicuous, a change in context had no effect on forgetting. (37 ref) (PsycINFO Database Record (c) 2006 APA, all rights reserved).