title: Environmental dynamics modulate covariation of choice and timing.
abstract: Response allocation between delayed reinforcers is presumably a function of the discrimination of those delays. In the present experiment, we analyzed the functional relation between response allocation and temporal discrimination across different environmental dynamics. Three pigeons pecked for food in a concurrent-chain schedule. Concurrent variable-interval initial links produced fixed-interval (FI) terminal links. Start and stop times, single-trial measures of temporal discrimination, were obtained from occasional 'no-food' terminal links. In dynamic, rapid-acquisition conditions, terminal links were FI 10s and 20s and the location of the initial link leading to the shorter terminal link varied unpredictably across sessions. In the static conditions, both terminal links were either "uniform" FI 15-s schedules or one terminal link was "fixed" at FI 10s and the other at 20s. Response allocation and start and stop times adjusted within sessions in dynamic conditions and across sessions of static conditions. Residuals from regressions of expected on programmed immediacy ratios were positively correlated to a greater magnitude in dynamic than static conditions. This change in residual covariation demonstrated that environmental dynamics modulated the relation between choice and timing.
authors.affiliation: Department of Psychology, West Virginia University, United States.
authors.forename: Shrinidhi
authors.initials: S
authors.lastname: Subramaniam
authors.affiliation: Department of Psychology, West Virginia University, United States. Electronic address: Elizabeth.Kyonka@mail.wvu.edu.
authors.forename: Elizabeth G E
authors.initials: EG
authors.lastname: Kyonka
mesh_terms: D000818:Animals; D002755:Choice Behavior / Q000502:physiology*; D010856:Columbidae; D003216:Conditioning, Operant / Q000502:physiology; D065786:Delay Discounting; D004193:Discrimination Learning / Q000502:physiology*; D004777:Environment; D005502:Food; D012055:Reinforcement Schedule
keywords: Concurrent chain; Conditioned reinforcement; Delay discrimination; Key peck; Pigeon; Rapid acquisition; Relative expected immediacy