Striatal dynamics explain duration judgments
- Champalimaud Centre for the Unknown, Portugal
Abstract
The striatum is an input structure of the basal ganglia implicated in several time-dependent functions including reinforcement learning, decision making, and interval timing. To determine whether striatal ensembles drive subjects' judgments of duration, we manipulated and recorded from striatal neurons in rats performing a duration categorization psychophysical task. We found that the dynamics of striatal neurons predicted duration judgments, and that simultaneously recorded ensembles could judge duration as well as the animal. Furthermore, striatal neurons were necessary for duration judgments, as muscimol infusions produced a specific impairment in animals' duration sensitivity. Lastly, we show that time as encoded by striatal populations ran faster or slower when rats judged a duration as longer or shorter, respectively. These results demonstrate that the speed with which striatal population state changes supports the fundamental ability of animals to judge the passage of time.
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Author details
Ethics
Animal experimentation: All experiments were in accordance with the European Union Directive 86/609/EEC and approved by the Portuguese Veterinary General Board (Direcção-Geral de Veterinária, project approval 014303 - 0420/000/000/2011)
Reviewing Editor
- Timothy Behrens, Oxford University, United Kingdom
Publication history
- Received: September 3, 2015
- Accepted: December 7, 2015
- Accepted Manuscript published: December 7, 2015 (version 1)
- Version of Record published: January 12, 2016 (version 2)
Copyright
© 2015, Gouvêa et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Striatal dynamics explain duration judgments
eLife 4:e11386.
https://doi.org/10.7554/eLife.11386
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