title: Discriminability of frequency of food or stimulus presentations in variable-time schedules.
abstract: Pigeons responded in a two-alternative forced-choice task in which reinforcement was dependent upon the frequency of events that occurred in an immediately preceding schedule sample. On a given trial the events were either brief food presentations or brief visual and auditory stimulus changes. High levels of stimulus control were obtained by food-presentation schedules only. Discriminative control by frequency or stimulus change was absent. Stimulus control by food frequency was decreased by the imposition of a delay period between the schedule sample and the choice. Moreover, stimulus control by food frequency was related to the ratio of food-presentation schedule pairs when novel schedules were presented in a transfer test.
mesh_terms: D000818:Animals; D010856:Columbidae; D003216:Conditioning, Operant; D004193:Discrimination Learning; D006801:Humans; D011939:Mental Recall; D012055:Reinforcement Schedule; D013998:Time Perception