Principles of operation of a cerebellar learning circuit
We provide behavioral evidence using monkey smooth pursuit eye movements for four principles of cerebellar learning. Using a circuit-level model of the cerebellum, we link behavioral data to learning's neural implementation. The four principles are: (1) early, fast, acquisition driven by climbing fiber inputs to the cerebellar cortex, with poor retention; (2) learned responses of Purkinje cells guide transfer of learning from the cerebellar cortex to the deep cerebellar nucleus, with excellent retention; (3) functionally different neural signals are subject to learning in the cerebellar cortex versus the deep cerebellar nuclei; and (4) negative feedback from the cerebellum to the inferior olive reduces the magnitude of the teaching signal in climbing fibers and limits learning. Our circuit-level model, based on these four principles, explains behavioral data obtained by strategically manipulating the signals responsible for acquisition and recall of direction learning in smooth pursuit eye movements across multiple timescales.
The data for each figure is included in a Figure Composer FYP file and can be viewed, exported, and further analyzed using the freely available Figure Composer tool (https://sites.google.com/a/srscicomp.com/datanav/figure-composer). This tool is platform agnostic and runs on Windows, Mac, and Linux systems. The source code used to generate the cerebellar model results (Figure 10) is included as a Jupyter notebook. This source code makes use of Julia but can be viewed without installing Julia.
Article and author information
National Institute of Neurological Disorders and Stroke (R01NS092623)
- Stephen G Lisberger
National Institute of Neurological Disorders and Stroke (F32NS103216)
- Nathan J Hall
National Eye Institute (K99-EY030528)
- David J Herzfeld
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Animal experimentation: All experimental procedures were performed in accordance with the Guide for the Care and Use of Laboratory Animals (1997) and had been approved in advance by the Institutional Animal Care and Use Committee at Duke University (Protocol A085-18-04).
- Jennifer L Raymond, Stanford University School of Medicine, United States
- Received: January 16, 2020
- Accepted: April 29, 2020
- Accepted Manuscript published: April 30, 2020 (version 1)
- Version of Record published: May 28, 2020 (version 2)
© 2020, Herzfeld 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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