Flexible motor sequence generation during stereotyped escape responses
- University of Science and Technology of China, China
- Mount Sinai Hospital, Canada
- University of Massachusetts Medical School, United States
- University of Toronto, Canada
Abstract
Complex animal behaviors arise from a flexible combination of stereotyped motor primitives. Here we use the escape responses of the nematode Caenorhabditis elegans to study how a nervous system dynamically explores the action space. The initiation of the escape responses is predictable: the animal moves away from a potential threat, a mechanical or thermal stimulus. But the motor sequence and the timing that follow are variable. We report that a feedforward excitation between neurons encoding distinct motor states underlies robust motor sequence generation, while mutual inhibition between these neurons controls the flexibility of timing in a motor sequence. Electrical synapses contribute to feedforward coupling whereas glutamatergic synapses contribute to inhibition. We conclude that C. elegans generates robust and flexible motor sequences by combining an excitatory coupling and a winner-take-all operation via mutual inhibition between motor modules.
Data availability
All data generated or analysed during this study are included in the manuscript .
Article and author information
Author details
Funding
National Science Foundation of China (NSFC-31471051 and NSFC-91632102)
- Yuan Wang
- Xiaoqian Zhang
- Qi Xin
- Jing Huo
- Tianqi Xu
- Yu Xie
- Quan Wen
Strategic Priority Research Program of Chinese Academy of Sciences (XDPB10)
- Yuan Wang
- Xiaoqian Zhang
- Qi Xin
- Jing Huo
- Tianqi Xu
- Yu Xie
- Quan Wen
CIHR (Foundation Scheme 154274)
- Wesley Hung
- Mei Zhen
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Wang 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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Flexible motor sequence generation during stereotyped escape responses
eLife 9:e56942.
https://doi.org/10.7554/eLife.56942
Further reading
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