Constraints on neural redundancy
- Carnegie Mellon University, United States
- Palo Alto Medical Foundation, United States
Abstract
Millions of neurons drive the activity of hundreds of muscles, meaning many different neural population activity patterns could generate the same movement. Studies have suggested that these redundant (i.e., behaviorally equivalent) activity patterns may be beneficial for neural computation. However, it is unknown what constraints may limit the selection of different redundant activity patterns. We leveraged a brain-computer interface, allowing us to define precisely which neural activity patterns were redundant. Rhesus monkeys made cursor movements by modulating neural activity in primary motor cortex. We attempted to predict the observed distribution of redundant neural activity. Principles inspired by work on muscular redundancy did not accurately predict these distributions. Surprisingly, the distributions of redundant neural activity and task-relevant activity were coupled, which enabled accurate predictions of the distributions of redundant activity. This suggests limits on the extent to which redundancy may be exploited by the brain for computation.
Data availability
Source data files have been provided for Figures 2-6. Code for analysis has been made available at https://github.com/mobeets/neural-redundancy-elife2018, with an MIT open source license (copy archived at https://github.com/elifesciences-publications/neural-redundancy-elife2018).
Article and author information
Author details
Funding
National Science Foundation (NCS BCS1533672)
- Aaron P Batista
- Byron M Yu
- Steven M Chase
National Institutes of Health (R01 HD071686)
- Aaron P Batista
- Byron M Yu
- Steven M Chase
National Science Foundation (Career award IOS1553252)
- Steven M Chase
National Institutes of Health (CRCNS R01 NS105318)
- Aaron P Batista
- Byron M Yu
Craig H. Neilsen Foundation (280028)
- Aaron P Batista
- Byron M Yu
- Steven M Chase
Simons Foundation (364994)
- Byron M Yu
Pennsylvania Department of Health (Research Formula Grant SAP 4100077048)
- Byron M Yu
- Steven M Chase
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 animal handling procedures were approved by the University of Pittsburgh Institutional Animal Care and Use Committee (protocol #15096685) in accordance with NIH guidelines. All surgery was performed under general anesthesia and strictly sterile conditions, and every effort was made to minimize suffering.
Copyright
© 2018, Hennig 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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Constraints on neural redundancy
eLife 7:e36774.
https://doi.org/10.7554/eLife.36774
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