355 — A Complete Electron Microscopy Volume of the Brain of Adult Drosophila melanogaster

This is one of the papers I’ve most looked forward to: The Bock Lab at Janelia has released a full female Drosophia brain imaged at nanometer resolution. Because of the huge scale of this data volume, the team had to develop new high-speed microscopy workflows that use modified electron microscopes to produce data at the rate necessary to make this project feasible.

After this imaging was complete, the researchers demonstrated one of many possible uses for this scale of data by tracing complete olfactory circuitry in the mushroom body of the fly brain. This reconstruction served as an indication that arbitrary circuitry can be traced in this dataset: The only cost is the manual annotation hours required. To that end, the researchers open-sourced the data — it is available here — for any researcher to download and use. #opendata!

This represents a large forward step in the field of connectomics, because it represents a shift from partial circuit reconstructions to whole-brain reconstruction on even nontrivial and unexplored networks. (Not to poo-poo C. elegans, but a 300 node network isn’t exactly big data.)

Despite 5% of the images being unusable as they came off of the scope (due to imaging errors or other artifacts), it was still possible to align the volume at high spatial acuity, meaning that many of the ‘cut’ processes might still be rescued.