Assessment of impulsivity using an automated, self-adjusting delay discounting procedure

Madison R. Carr, Yvar van Mourik, Paula Gómez-Sotres, Marcello Solinas, Taco J. de Vries, Tommy Pattij*

*Corresponding author for this work

Research output: Contribution to JournalArticleAcademicpeer-review

Abstract

Modelling delay discounting behavior in rodents is important for understanding the neurobiological mechanisms underlying cognitive control and associated impulsivity disorders. Conventional rodent delay discounting procedures require extensive training and frequent experimenter interaction, as rodents are tested in separate operant chambers away from their home cage. To address these limitations, we adapted and characterize here a self-adjusting delay discounting procedure to an automated CombiCage setup. Rodents were trained during the most active phase of the light-dark cycle, completing 120 trials daily. During each session, we measured large reward preference, mean adjusted delay, and trial participation across multiple delays. Results showed that rodents exhibited discounting behavior after two weeks, with performance stability increasing at 7 weeks training with delay. We also evaluated the influence of altering the consecutive choice criteria (ccc), number of trial choices for a delay step to adjust up or down. Lower ccc (3 vs 8) increased both the number of delay steps encountered per session and task participation. Additionally, we examined the effects of pharmacological interventions, including the psychostimulant amphetamine and the dopamine D1 receptor antagonist, SCH23390. A high dose amphetamine reduced preference for large immediate and short delayed rewards and decreased the mean adjusted delay in a non-dose dependent manner, while SCH23390 did not affect task performance. Together, this novel automated self-adjusting procedure enables high-throughput collection of delay discounting data, with potential applications for investigating impulsivity across the lifespan. However, the current extended session design may limit its suitability for pharmacological evaluations.

Original languageEnglish
Article number115405
Pages (from-to)1-8
Number of pages8
JournalBehavioural Brain Research
Volume480
Early online date18 Dec 2024
DOIs
Publication statusE-pub ahead of print - 18 Dec 2024

Bibliographical note

Publisher Copyright:
© 2024 The Authors

Keywords

  • Amphetamine
  • Animal model
  • Automated
  • Delay discounting
  • Homecage
  • Impulsivity
  • Self-adjusting

Fingerprint

Dive into the research topics of 'Assessment of impulsivity using an automated, self-adjusting delay discounting procedure'. Together they form a unique fingerprint.

Cite this