Explicit information reduces discounting behavior in monkeys.

Published

Journal Article

Animals are notoriously impulsive in common laboratory experiments, preferring smaller, sooner rewards to larger, delayed rewards even when this reduces average reward rates. By contrast, the same animals often engage in natural behaviors that require extreme patience, such as food caching, stalking prey, and traveling long distances to high-quality food sites. One possible explanation for this discrepancy is that standard laboratory delay discounting tasks artificially inflate impulsivity by subverting animals' common learning strategies. To test this idea, we examined choices made by rhesus macaques in two variants of a standard delay discounting task. In the conventional variant, post-reward delays were uncued and adjusted to render total trial length constant; in the second, all delays were cued explicitly. We found that measured discounting was significantly reduced in the cued task, with discount parameters well below those reported in studies using the standard uncued design. When monkeys had complete information, their decisions were more consistent with a strategy of reward rate maximization. These results indicate that monkeys, and perhaps other animals, are more patient than is normally assumed, and that laboratory measures of delay discounting may overstate impulsivity.

Full Text

Duke Authors

Cited Authors

  • Pearson, JM; Hayden, BY; Platt, ML

Published Date

  • January 2010

Published In

Volume / Issue

  • 1 /

Start / End Page

  • 237 -

PubMed ID

  • 21833291

Pubmed Central ID

  • 21833291

Electronic International Standard Serial Number (EISSN)

  • 1664-1078

International Standard Serial Number (ISSN)

  • 1664-1078

Digital Object Identifier (DOI)

  • 10.3389/fpsyg.2010.00237

Language

  • eng