Single caudate neurons encode temporally discounted value for formulating motivation for action
- National Institutes for Quantum and Radiological Science and Technology, Japan
- Kyoto University, Japan
- NIMH/NIH/DHHS, Bethesda, MD 20814, USA, United States
Abstract
The term ‘temporal discounting’ describes both choice preferences and motivation for delayed rewards. Here we show that neuronal activity in the dorsal part of the primate caudate head (dCDh) signals the temporally discounted value needed to compute the motivation for delayed rewards. Macaque monkeys performed an instrumental task, in which visual cues indicated the forthcoming size and delay duration before reward. Single dCDh neurons represented the temporally discounted value without reflecting changes in the animal’s physiological state. Bilateral pharmacological or chemogenetic inactivation of dCDh markedly distorted the normal task performance based on the integration of reward size and delay, but did not affect the task performance for different reward sizes without delay. These results suggest that dCDh is involved in encoding the integrated multidimensional information critical for motivation.
Data availability
We provide source data to reproduce the main results of the paper presented in Figures 1, 5, 7 and 8.
Article and author information
Author details
Takafumi Minamimoto
Funding
Japan Society for the Promotion of Science (JP18H04037,JP20H05955)
- Takafumi Minamimoto
Japan Agency for Medical Research and Development (JP20dm0107146)
- Takafumi Minamimoto
Japan Agency for Medical Research and Development (JP20dm0207077)
- Masahiko Takada
Japan Agency for Medical Research and Development (JP20dm0307021)
- Ken-ichi Inoue
National Institute of Mental Health (Annual Report ZIAMH-2619)
- Barry J Richmond
Primate Research Institute, Kyoto University (2020-A-6)
- Takafumi Minamimoto
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All surgical and experimental procedures were approved by the National Institutes for Quantum and Radiological Science and Technology (11-1038-11) and by the Animal Care and Use Committee of the National Institute of Mental Health (Annual Report ZIAMH002619), and were in accordance with the Institute of Laboratory Animal Research Guide for the Care and Use of Laboratory Animals.
Copyright
This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.
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