title: Feature-positive and feature-negative learning in the rhesus monkey and pigeon.
abstract: In separate experiments four monkeys and eight pigeons were presented with displays containing one red and two green keys and displays containing three green keys. During feature-positive phases, responses to displays containing the one red and two green keys were reinforced on a fixed-ratio schedule, while responses to displays containing the three green keys were never reinforced. During feature-negative phases, only responses to the three green key displays were reinforced. For monkeys in Experiment 1, both between and within subject analyses indicated that the learning of feature-positive discriminations was superior to the learning of feature-negative discriminations. The within subject analysis further revealed that performance on a feature-positive discrimination was retarded following exposure to a feature-negative discrimination, while performance on a feature-negative discrimination was enhanced following exposure to a feature-positive discrimination. Experiment 2 replicated the essential aspects of these reversal effects in four experimental pigeons. Evidence that these reversal effects were not simply a function of time was provided by four control birds exposed to only a feature-positive or feature-negative discrimination.
mesh_terms: D000818:Animals; D003118:Color Perception; D010856:Columbidae; D003216:Conditioning, Operant; D004193:Discrimination Learning; D005260:Female; D008253:Macaca mulatta; D008297:Male; D012055:Reinforcement Schedule; D012193:Reversal Learning