title: Simultaneous discrimination learning in pigeons: value of S- affects the relative value of its associated S+.
abstract: In a simple simultaneous discrimination involving a positive stimulus (S+) and a negative stimulus (S-), it has been hypothesized that positive value can transfer from the S+ to the S- (thus increasing the relative value of the S-) and also that negative value can transfer from the S- to the S+ (thus diminishing the relative value of the S+; Fersen, Wynne, Delius, & Staddon, 1991). Evidence for positive value transfer has been reported in pigeons (e.g. Zentall & Sherburne, 1994). The purpose of the present experiments was to determine, in a simultaneous discrimination, whether the S- diminishes the value of the S+ or the S- is contrasted with the S+ (thus enhancing the value of the S+). In two experiments, we found evidence for contrast, rather than value transfer, attributable to simultaneous discrimination training. Thus, not only does the S+ appear to enhance the value of the S-, but the S- appears to enhance rather than reduce the value of the S+.
authors.affiliation: Department of Psychology, University of Kentucky, Lexington 40506-0044, USA.
authors.forename: T S
authors.initials: TS
authors.lastname: Clement
authors.forename: J E
authors.initials: JE
authors.lastname: Weaver
authors.forename: L M
authors.initials: LM
authors.lastname: Sherburne
authors.forename: T R
authors.initials: TR
authors.lastname: Zentall
mesh_terms: D000818:Animals; D001288:Attention; D003118:Color Perception; D010856:Columbidae; D004193:Discrimination Learning; D005260:Female; D008297:Male; D009042:Motivation; D009949:Orientation; D014163:Transfer, Psychology