Cerebellar implementation of movement sequences through feedback
- University of Texas at Austin, United States
Abstract
Most movements are not unitary, but are comprised of sequences. Although patients with cerebellar pathology display severe deficits in the execution and learning of sequences1,2, most of our understanding of cerebellar mechanisms has come from analyses of single component movements. Eyelid conditioning is a cerebellar-mediated behavior that provides the ability to control and restrict inputs to the cerebellum through stimulation of mossy fibers. We utilized this advantage to test directly how the cerebellum can learn a sequence of inter-connected movement components in rabbits. We show that the feedback signals from one component are sufficient to serve as a cue for the next component in the sequence. In vivo recordings from Purkinje cells demonstrated that all components of the sequence were encoded similarly by cerebellar cortex. These results provide a simple yet general framework for how the cerebellum can use simple associate learning processes to chain together a sequence of appropriately timed responses.
Data availability
All data needed to evaluate the conclusions in the paper are present in the paper and/or the Supplementary Figures. Source data is provided for Figures 2-8.
Article and author information
Author details
Funding
National Institute of Mental Health (MH 46904)
- Michael Dean Mauk
National Institute of Neurological Disorders and Stroke (NS 98308)
- Michael Dean Mauk
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Indira M Raman, Northwestern University, United States
Ethics
Animal experimentation: Treatment of animals and surgical procedures were in accordance with National Institutes of Health guidelines and an institutional animal care and use committee (IACUC) protocol (#AUP-2015-00137) of the University of Texas at Austin. Every effort was made to minimize suffering.
Version history
- Received: April 11, 2018
- Accepted: July 28, 2018
- Accepted Manuscript published: July 31, 2018 (version 1)
- Version of Record published: August 23, 2018 (version 2)
- Version of Record updated: August 24, 2018 (version 3)
Copyright
© 2018, Khilkevich 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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Cerebellar implementation of movement sequences through feedback
eLife 7:e37443.
https://doi.org/10.7554/eLife.37443
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