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BoutonNet: an automatic method to detect anterogradely labeled presynaptic boutons in brain tissue sections
Fillan S Grady1, Shantelle A Graff1, Georgina M Aldridge1
1Department of Neurology, Iowa Neuroscience Institute, University of Iowa, PBDB 1320, 169 Newton Rd, Iowa City, IA, 52246, USA.
Brain Structure & Function
|June 1, 2022
Summary
Neuroscientists developed BoutonNet, an automated pipeline for identifying synaptic boutons in brain tissue. This open-source tool enables large-scale, quantitative analysis of neural connections with high accuracy.
Area of Science:
- Neuroscience
- Computational Biology
- Histology
Background:
- Synapses are the fundamental units of the nervous system, formed by neuronal axons.
- Analyzing synaptic output requires advanced methods like genetic anterograde tracing.
- Current analysis methods for large datasets are manual, costly, and lack quality.
Purpose of the Study:
- To develop an optimized pipeline for identifying anterogradely labeled presynaptic boutons.
- To create an automated detection method, BoutonNet, for analyzing brain tissue sections.
- To enable quantitative, whole-brain scale analysis of synaptic structures.
Main Methods:
- A histologic pipeline was optimized for high-sensitivity, low-background labeling of boutons.
- BoutonNet, a two-step detector, was developed using intensity-based proposals and neural network confirmation.
- The method was validated against expert annotations on independent datasets.
Main Results:
- The developed pipeline achieves high sensitivity and low background for bouton labeling.
- BoutonNet accurately detects labeled presynaptic boutons in slide-scanned tissue sections.
- BoutonNet's performance is comparable to human inter-rater variance.
Conclusions:
- BoutonNet provides a cost-effective and high-quality automated solution for bouton detection.
- This open-source technique facilitates quantitative analysis of synaptic units at a whole-brain scale.
- The method advances the study of neural circuitry and brain function.

