Dynamic modulation of activity in cerebellar nuclei neurons during pavlovian eyeblink conditioning in mice
- Erasmus Medical Center, Netherlands
- Baylor College of Medicine, United States
Abstract
While research on the cerebellar cortex is crystallizing our understanding of its function in learning behavior, many questions surrounding its downstream targets remain. Here, we evaluate the dynamics of cerebellar interpositus nucleus (IpN) neurons over the course of Pavlovian eyeblink conditioning. A diverse range of learning-induced neuronal responses was observed, including increases and decreases in activity during the generation of conditioned blinks. Trial-by-trial correlational analysis and optogenetic manipulation demonstrate that facilitation in the IpN drives the eyelid movements. Adaptive facilitatory responses are often preceded by acquired transient inhibition of IpN activity that, based on latency and effect, appear to be driven by complex spikes in cerebellar cortical Purkinje cells. Likewise, during reflexive blinks to periocular stimulation, IpN cells show excitation-suppression patterns that suggest a contribution of climbing fibers and their collaterals. These findings highlight the integrative properties of subcortical neurons at the cerebellar output stage mediating conditioned behavior.
Data availability
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Eyelid behavior and spike activity of cerebellar interpositus nucleus neurons during eyeblink conditioning in awake behaving micePublicly available at the Collaborative Research in Computational Neuroscience (http://crcns.org/).
Article and author information
Author details
Funding
Nederlandse Organisatie voor Wetenschappelijk Onderzoek
- Zhenyu Gao
European Research Council
- Chris I De Zeeuw
National Institutes of Health
- Javier F Medina
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: The experiments were approved by the institutional animal welfare committee (Erasmus MC, Rotterdam, The Netherlands). All surgery was performed under isoflurane anaesthesia, and every effort was made to minimize suffering.
Copyright
© 2017, ten Brinke 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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Dynamic modulation of activity in cerebellar nuclei neurons during pavlovian eyeblink conditioning in mice
eLife 6:e28132.
https://doi.org/10.7554/eLife.28132
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