title: Sensitivity to delay is affected by magnitude of reinforcement in rats.
abstract: Previous research has provided discrepant results about how reinforcement delay and magnitude are combined to determine the value of the alternatives in concurrent-chains schedules. In the present experiment, we analyzed a possible interaction between these characteristics of reinforcement, employing a two component concurrent-chains schedule, with rats as experimental subjects. Non-independent VI schedules were presented in the initial links of each component. In the terminal links, the following pairs of delays to reinforcement were presented in 4 conditions: 2-28, 6-24, 24-6, 28-2s (fixed time schedules for a group, fixed interval schedules for the other). Magnitude of reinforcement was maintained constant within components: one pellet for one component, and four pellets for the other. The results indicated that in both groups, the sensitivity to delay - calculated according to the generalized matching law - was higher in the component with the larger reinforcer. This result is in contrast with those reported in the literature of temporal discounting with human participants.
authors.affiliation: Facultad de Psicología, Universidad Nacional Autónoma de México, México D.F. 04510, Mexico. vladord@unam.mx
authors.forename: Vladimir
authors.initials: V
authors.lastname: Orduña
authors.forename: Lourdes
authors.initials: L
authors.lastname: Valencia-Torres
authors.forename: Guadalupe
authors.initials: G
authors.lastname: Cruz
authors.forename: Arturo
authors.initials: A
authors.lastname: Bouzas
mesh_terms: D000818:Animals; D003216:Conditioning, Operant; D008297:Male; D051381:Rats; D012055:Reinforcement Schedule; D012054:Reinforcement, Psychology; D013997:Time Factors
keywords: Concurrent chains; Generalized matching law; Magnitude of reinforcement; Rats; Sensitivity to delay; Temporal discounting