title: Human risky choice: delay sensitivity depends on reinforcer type.
abstract: The present study was designed to help bridge the methodological gap between human and nonhuman animal research in delay-based risky choice. In Part 1, 4 adult human subjects made repeated choices between variable-time and fixed-time schedules of 30-s video clips. Both alternatives had equal mean delays of 15 s, 30 s, or 60 s. Three of 4 subjects strongly preferred the variable-delay alternative across all conditions. In Part 2, these 3 subjects were then provided pairwise choices between 2 variable-time schedules with different delay distributions. Subjects generally preferred the variable-delay distributions with a higher probability of short-reinforcer delays, consistent with accounts based on nonlinear discounting of delayed reinforcement. There was only weak correspondence between experimental results and verbal reports. The overall pattern of results is inconsistent with prior risky choice research with human subjects but is consistent with prior results with nonhuman subjects, suggesting that procedural differences may be a critical factor determining risk-sensitivity across species.
authors.affiliation: Department of Psychology, University of Florida, Gainesville, FL 32611, USA. mlocey@ufl.edu
authors.forename: Matthew L
authors.initials: ML
authors.lastname: Locey
authors.forename: Cynthia J
authors.initials: CJ
authors.lastname: Pietras
authors.forename: Timothy D
authors.initials: TD
authors.lastname: Hackenberg
mesh_terms: D002755:Choice Behavior; D006801:Humans; D008297:Male; D012054:Reinforcement, Psychology; D012309:Risk-Taking; D012919:Social Behavior; D011795:Surveys and Questionnaires; D013997:Time Factors; D014743:Videotape Recording; D055815:Young Adult