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Updated: Jun 22, 2026
07:47
Measuring Delay Discounting in Humans Using an Adjusting Amount Task
Published on: January 9, 2016
Reward contrast in delay and probability discounting.
Zhijie Dai1, Randolph C Grace, Simon Kemp
1University of Canterbury, Christchurch, New Zealand.
Learning & Behavior
|June 23, 2009
Summary
Reward contrast significantly impacts decision-making. Prior larger rewards decrease the subjective value of subsequent smaller rewards, affecting delay and probability discounting for monetary choices.
Area of Science:
- Decision Neuroscience
- Behavioral Economics
- Cognitive Psychology
Background:
- Understanding how subjective value is determined is crucial for behavioral economics.
- Reward contrast, where the perceived value of a stimulus is influenced by preceding stimuli, is a known phenomenon.
Purpose of the Study:
- To investigate the influence of reward contrast on choices involving delayed and probabilistic monetary outcomes.
- To determine if subjective value of intermediate rewards changes based on preceding larger or smaller rewards.
Main Methods:
- Experiment 1: Between-subjects design comparing delay and probability discounting rates for intermediate rewards after exposure to high ($5,000) or low ($50) anchor rewards.
- Experiment 2: Within-subjects design assessing the present value of intermediate rewards ($475/$525) after blocks of high or low anchor rewards, manipulating delay and probability.
Main Results:
- Experiment 1 showed higher delay discounting for the $500 outcome after $5,000 anchors compared to $50 anchors, with inverse results for probability discounting.
- Experiment 2 revealed that the present value of intermediate rewards was higher following smaller anchor rewards ($50) than larger ones ($5,000) for delay discounting, and vice versa for probability discounting.
Conclusions:
- Reward contrast effects were confirmed, demonstrating that subjective value of monetary rewards is influenced by prior reward magnitude.
- The findings suggest that the perceived value of a reward is relative and inversely proportional to the magnitude of preceding rewards.
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