Neuromodulatory connectivity defines the structure of a behavioral neural network
- National Institute of Mental Health, United States
- National Institute of General Medical Sciences, United States
Abstract
Neural networks are typically defined by their synaptic connectivity, yet synaptic wiring diagrams often provide limited insight into network function. This is due partly to the importance of non-synaptic communication by neuromodulators, which can dynamically reconfigure circuit activity to alter its output. Here we systematically map the patterns of neuromodulatory connectivity in a network that governs a developmentally critical behavioral sequence in Drosophila. This sequence, which mediates pupal ecdysis, is governed by the serial release of several key factors, which act both somatically as hormones and within the brain as neuromodulators. By identifying and characterizing the functions of the neuronal targets of these factors, we find that they define hierarchically organized layers of the network controlling the pupal ecdysis sequence: a modular input layer, an intermediate central pattern generating layer, and a motor output layer. Mapping neuromodulatory connections in this system thus defines the functional architecture of the network.
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Author details
Funding
National Institute of Mental Health (MH002800-15)
- Benjamin H White
National Institute of General Medical Sciences (FI2 GM117582)
- Amicia D Elliott
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.
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Neuromodulatory connectivity defines the structure of a behavioral neural network
eLife 6:e29797.
https://doi.org/10.7554/eLife.29797
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