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Connectome quality converges predictably to reveal optimal stopping points during proofreading
Hannah Martinez1, Jordan K Matelsky1,2, Daniel Xenes1
1Johns Hopkins Applied Physics Laboratory, Laurel, MD, USA.
Biorxiv : the Preprint Server for Biology
|July 10, 2026
Summary
Proofreading errors in brain reconstructions from electron microscopy (EM) are costly. This study introduces a fast method to estimate proofreading progress, determining when neuronal network analysis can begin without needing ground truth data.
Area of Science:
- Neuroscience
- Computational Biology
- Microscopy
Background:
- Volumetric electron microscopy (EM) generates high-resolution brain tissue reconstructions.
- Automated segmentation in EM pipelines introduces errors requiring manual proofreading.
- Proofreading is a major cost and bottleneck in reconstructing neuronal networks.
Purpose of the Study:
- To develop a method for estimating connectomic proofreading progress.
- To provide a quantitative criterion for determining proofreading completeness.
- To reduce uncertainty in planning and budgeting proofreading efforts.
Main Methods:
- Utilizing global graph invariants that predictably converge to asymptotic limits.
- Estimating proofreading progress without prior knowledge of ground truth.
- Applying the method to zebrafish spinal cord and Drosophila melanogaster hemibrain datasets.
Main Results:
- Global graph invariants show predictable convergence patterns with increased proofreading.
- This convergence provides a quantitative 'pencils down' criterion for proofreading.
- The method effectively informs the completion status of connectomic reconstruction.
Conclusions:
- A fast, inexpensive method accurately estimates connectomic proofreading progress.
- This approach enables data owners to predict and budget necessary proofreading.
- The findings facilitate more efficient and reliable neuronal network reconstruction for scientific analysis.
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