Generative network modeling reveals quantitative definitions of bilateral symmetry exhibited by a whole insect brain connectome
- Johns Hopkins University, United States
- University of Cambridge, United Kingdom
Abstract
Comparing connectomes can help explain how neural connectivity is related to genetics, disease, development, learning, and behavior. However, making statistical inferences about the significance and nature of differences between two networks is an open problem, and such analysis has not been extensively applied to nanoscale connectomes. Here, we investigate this problem via a case study on the bilateral symmetry of a larval Drosophila brain connectome. We translate notions of'bilateral symmetry' to generative models of the network structure of the left and right hemispheres, allowing us to test and refine our understanding of symmetry. We find significant differences in connection probabilities both across the entire left and right networks and between specific cell types. By rescaling connection probabilities or removing certain edges based on weight, we also present adjusted definitions of bilateral symmetry exhibited by this connectome. This work shows how statistical inferences from networks can inform the study of connectomes, facilitating future comparisons of neural structures.
Data availability
All code used for analysis is available at https://github.com/neurodata/bilateral-connectome, and the version for this submission is archived at https://doi.org/10.5281/zenodo.7733481.All data analyzed in this study were generated in Winding, Pedigo et al. "The connectome of an insect brain," Science (2023) https://www.science.org/doi/10.1126/science.add9330.These data are also included for convenience in the code repository linked above and as Figure 1 - Source Data 1.
Article and author information
Author details
Joshua T Vogelstein
Funding
National Science Foundation (DGE1746891)
- Benjamin D Pedigo
National Science Foundation (1942963)
- Joshua T Vogelstein
National Science Foundation (2014862)
- Joshua T Vogelstein
National Institutes of Health (1RF1MH123233-01)
- Carey E Priebe
- Joshua T Vogelstein
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2023, Pedigo 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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Generative network modeling reveals quantitative definitions of bilateral symmetry exhibited by a whole insect brain connectome
eLife 12:e83739.
https://doi.org/10.7554/eLife.83739
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