Distributed coding of duration in rodent prefrontal cortex during time reproduction
As we interact with the external world, we judge magnitudes from sensory information. The estimation of magnitudes has been characterized in primates, yet it is largely unexplored in non-primate species. Here we use time interval reproduction to study rodent behavior and its neural correlates in the context of magnitude estimation. We show that gerbils display primate-like magnitude estimation characteristics in time reproduction. Most prominently their behavioral responses show a systematic overestimation of small stimuli and an underestimation of large stimuli, often referred to as regression effect. We investigated the underlying neural mechanisms by recording from medial prefrontal cortex and show that the majority of neurons respond either during the measurement or the reproduction of a time interval. Cells that are active during both phases display distinct response patterns. We categorize the neural responses into multiple types and demonstrate that only populations with mixed responses can encode the bias of the regression effect. These results help unveil the organizing neural principles of time reproduction and perhaps magnitude estimation in general.
Raw data for this study are available at https://doi.org/10.12751/g-node.tarvrs (Henke et al., 2021).In addition, source data are given when mentioned in the respective figures.
Article and author information
Bundesministerium für Bildung, Wissenschaft und Forschung (01GQ1004A)
- Josephine Henke
- Kay Thurley
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Animal experimentation: All experiments were approved according to national and European guidelines on animal welfare (Reg. von Oberbayern, District Government of Upper Bavaria; reference numbers: AZ 55.2-1-54-2532-10-11 and AZ 55.2-1-54-2532-70-2016).
- Hugo Merchant, National Autonomous University of Mexico, Mexico
- Received: June 24, 2021
- Accepted: December 14, 2021
- Accepted Manuscript published: December 23, 2021 (version 1)
- Version of Record published: January 24, 2022 (version 2)
© 2021, Henke 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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