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Updated: May 31, 2026
07:47
Measuring Delay Discounting in Humans Using an Adjusting Amount Task
Published on: January 9, 2016
Effects of selective dopaminergic compounds on a delay-discounting task
Mikhail N Koffarnus1, Amy H Newman, Peter Grundt
1Behavioral Pharmacology Research Unit, Johns Hopkins University School of Medicine, Baltimore, Maryland 21224, USA. mkoffar1@jhmi.edu
Behavioural Pharmacology
|June 23, 2011
Summary
Impulsivity, linked to dopamine, was studied using delay-discounting tasks in rats. Certain dopamine receptor drugs altered choices, but none reduced impulsivity, suggesting further research is needed for therapeutic applications.
Area of Science:
- Neuroscience
- Behavioral Pharmacology
Background:
- Impulsivity is a multidimensional trait involving distinct behaviors.
- Dopaminergic systems are crucial for impulsive behavior in humans and animals.
- Impulsive choice, prioritizing immediate rewards, is studied via delay-discounting tasks.
Purpose of the Study:
- To investigate the effects of various dopaminergic drugs on impulsive choice.
- To assess receptor-selective dopaminergic agonists, antagonists, and transporter ligands.
- To understand the role of dopamine in immediate versus delayed reward choices.
Main Methods:
- Delay-discounting procedures were employed in Sprague-Dawley rats.
- The effects of 11 different dopaminergic compounds were evaluated.
- Behavioral changes in immediate vs. delayed reward choices were measured.
Main Results:
- The D1-like antagonist SCH 23390 and D4 partial agonist ABT-724 selectively increased impulsive choice.
- These effects may stem from their prefrontal cortex neuronal localization.
- No tested selective agonists or antagonists effectively reduced impulsive choice.
Conclusions:
- Dopamine pathways in the prefrontal cortex influence impulsive choice.
- Current selective dopaminergic agents may not be suitable for treating impulse-control disorders.
- Further research is required to explore therapeutic potential of dopaminergic modulation.
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