Potentiation of cerebellar Purkinje cells facilitates whisker reflex adaptation through increased simple spike activity
Abstract
Cerebellar plasticity underlies motor learning. However, how the cerebellum operates to enable learned changes in motor output is largely unknown. We developed a sensory-driven adaptation protocol for reflexive whisker protraction and recorded Purkinje cell activity from crus 1 and 2 of awake mice. Before training, simple spikes of individual Purkinje cells correlated during reflexive protraction with the whisker position without lead or lag. After training, simple spikes and whisker protractions were both enhanced with the spiking activity now leading behavioral responses. Neuronal and behavioral changes did not occur in two cell-specific mouse models with impaired long-term potentiation at their parallel fiber to Purkinje cell synapses. Consistent with cerebellar plasticity rules, increased simple spike activity was prominent in cells with low complex spike response probability. Thus, potentiation at parallel fiber to Purkinje cell synapses may contribute to reflex adaptation and enable expression of cerebellar learning through increases in simple spike activity.
Data availability
Source data files for all box plots are provided, i.e. for Figures 3, 5 and 8 and for Figure supplements 1-S2, 5-S1, 5-S2, 5-S3, 5-S4, 8-S1 and 8-S2.
Article and author information
Author details
Funding
Nederlandse Organisatie voor Wetenschappelijk Onderzoek (ALW)
- Chris I De Zeeuw
ZonMw
- Chris I De Zeeuw
European Research Council (ERC-Advanced Grant)
- Chris I De Zeeuw
European Research Council (ERC-PoC)
- Chris I De Zeeuw
China Scholarship Council (2010623033)
- Chiheng Ju
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 experimental procedures were approved a priori by an independent animal ethical committee (DEC-Consult, Soest, The Netherlands) as required by Dutch law and conform the relevant institutional regulations of the Erasmus MC and Dutch legislation on animal experimentation. Permissions were obtained under the following license numbers: EMC2656, EMC2933, EMC2998, EMC3001, EMC3168 and AVD101002015273.
Copyright
© 2018, Romano 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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