Conservation of preparatory neural events in monkey motor cortex regardless of how movement is initiated
Abstract
A time-consuming preparatory stage is hypothesized to precede voluntary movement. A putative neural substrate of motor preparation occurs when a delay separates instruction and execution cues. When readiness is sustained during the delay, sustained neural activity is observed in motor and premotor areas. Yet whether delay-period activity reflects an essential preparatory stage is controversial. In particular, it has remained ambiguous whether delay-period-like activity appears before non-delayed movements. To overcome that ambiguity, we leveraged a recently developed analysis method that parses population responses into putatively preparatory and movement-related components. We examined cortical responses when reaches were initiated after an imposed delay, at a self-chosen time, or reactively with low latency and no delay. Putatively preparatory events were conserved across all contexts. Our findings support the hypothesis that an appropriate 'preparatory state' is consistently achieved before movement onset. However, our results reveal that this process can consume surprisingly little time.
Data availability
The data supporting this work is available via Dryad (http://dx.doi.org/10.5061/dryad.cf66jb7).
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Data from: Conservation of preparatory neural events in monkey motor cortex regardless of how movement is initiatedAvailable at Dryad Digital Repository under a CC0 Public Domain Dedication.
Article and author information
Author details
Funding
Alfred P. Sloan Foundation
- Mark M Churchland
Kavli Foundation
- Mark M Churchland
Klingenstein Third Generation Foundation
- Mark M Churchland
Kinship Foundation
- Mark M Churchland
National Institute of Neurological Disorders and Stroke (NS092350)
- Antonio Homero Lara
Gatsby Charitable Foundation
- John Cunningham
- Mark M Churchland
Simons Foundation (SCGB#325171)
- John Cunningham
- Mark M Churchland
Simons Foundation (SCGB#325233)
- John Cunningham
- Mark M Churchland
Grossman Center for the Statistics of Mind
- John Cunningham
- Mark M Churchland
McKnight Endowment Fund for Neuroscience
- John Cunningham
- Mark M Churchland
National Institute of Neurological Disorders and Stroke (DP2 NS083037)
- Mark M Churchland
National Institute of Neurological Disorders and Stroke (R01NS100066)
- John Cunningham
- Mark M Churchland
National Institute of Neurological Disorders and Stroke (NS104649)
- John Cunningham
- Mark M Churchland
National Eye Institute (P30 EY-019007)
- Mark M Churchland
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 procedures were in accord with the US National Institutes of Health guidelines and were approved by the Columbia University Institutional Animal Care and Use Committee (AC-AAAQ7409).
Copyright
© 2018, Lara 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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