id,reconstruction,group,organism,stage,scope,publication_year,neurons,count_type,synapses,synapse_basis,neuron_to_neuron_edges,volume_mm3,method,teravoxels,raw_data_tb,proofreading_person_years,authors,first_author_institution,last_author_institution,last_author_country,open_access,doi,status,note
white1986,C. elegans hermaphrodite (White et al.),worm,Caenorhabditis elegans,adult hermaphrodite,whole nervous system,1986,302,neurons,5000,"about 5,000 chemical synapses (plus ~2,000 neuromuscular junctions, ~600 gap junctions)",,,Serial-section EM,,,,4,MRC Laboratory of Molecular Biology,MRC Laboratory of Molecular Biology,GB,closed,10.1098/rstb.1986.0056,peer-reviewed,"Original wiring diagram; the paper is behind a paywall, abstract read."
helmstaedter2013,"Mouse retina, inner plexiform layer (Helmstaedter et al.)",mouse,Mus musculus,mouse,part of the retina,2013,950,neurons,,"contacts, not counted as synapses in the abstract",,,Serial block-face SEM,,,,6,Max Planck Society,Max Planck Society,DE,closed,10.1038/nature12346,peer-reviewed,
kasthuri2015,Mouse neocortex fragment (Kasthuri et al.),mouse,Mus musculus,mouse,sub-volume of neocortex,2015,,neurons,,not read (Cell text not available to us),,0.0015,Serial-section EM,,,,21,Harvard University,Harvard University,US,bronze,10.1016/j.cell.2015.06.054,peer-reviewed,"Volume (about 1500 cubic micrometres) read in the Motta et al. preprint, which cites it; no neuron or synapse count recorded."
ryan2016,Ciona larva CNS (Ryan et al.),other,Ciona intestinalis (sea squirt larva),larva,whole central nervous system,2016,177,neurons,6618,"6,618 synapses incl. 1,772 neuromuscular junctions (plus 1,206 gap junctions)",,,Serial-section EM,,,,3,Dalhousie University,Dalhousie University,CA,gold,10.7554/eLife.16962,peer-reviewed,
cook2019h,C. elegans hermaphrodite (Cook et al.),worm,Caenorhabditis elegans,adult hermaphrodite,"whole animal, incl. muscles",2019,302,neurons,,"neuron-to-neuron edges: 4,887 chemical + 1,447 gap junction (no synapse count in the text)",4887,,Serial-section EM,,,,14,Albert Einstein College of Medicine,Albert Einstein College of Medicine,US,green,10.1038/s41586-019-1352-7,peer-reviewed,Re-annotation of the 1970s-80s micrographs plus new male head series.
cook2019m,C. elegans male (Cook et al.),worm,Caenorhabditis elegans,adult male,"whole animal, incl. muscles",2019,385,neurons,,"neuron-to-neuron edges: 5,315 chemical + 1,755 gap junction",5315,,Serial-section EM,,,,14,Albert Einstein College of Medicine,Albert Einstein College of Medicine,US,green,10.1038/s41586-019-1352-7,peer-reviewed,
motta2019,"Mouse barrel cortex, layer 4 (Motta et al.)",mouse,Mus musculus,mouse,"block of layer 4, somatosensory cortex",2019,,neurons,,"6,979 axons and 3,719 postsynaptic neurites analysed (preprint)",,0.0005,Serial block-face SEM,,,,10,Max Planck Institute for Brain Research,Max Planck Institute for Brain Research,DE,green,10.1126/science.aay3134,peer-reviewed,"About 4,000 human work hours reported."
scheffer2020,Fruit fly hemibrain (Scheffer et al.),fly,Drosophila melanogaster,single female,about half of the central brain,2020,25000,neurons,20000000,"""about 20 million chemical synapses"" (9.5 million T-bars, 64 million postsynaptic densities)",,,FIB-SEM,26,,50,108,Howard Hughes Medical Institute,Howard Hughes Medical Institute,US,gold,10.7554/eLife.57443,peer-reviewed,Person-years as reported in the FlyWire paper.
witvliet2021,"C. elegans, 8 animals birth to adult (Witvliet et al.)",worm,Caenorhabditis elegans,"8 isogenic animals, L1 to adult",brain (nerve ring and ventral ganglion),2021,204,cells,8000,"about 8,000 chemical synapses in adults (about 1,300 at birth); 204 cells in the brain at birth",,,Serial-section EM,,,,16,Mount Sinai Hospital,Mount Sinai Hospital,CA,green,10.1038/s41586-021-03778-8,peer-reviewed,The 204 is the cell count at birth; the adult cell count is not given in the text we read.
svara2022,"Larval zebrafish brain, 208 neurons (Svara et al.)",zebrafish,Danio rerio,larva,whole brain imaged; 208 neurons reconstructed,2022,208,neurons,1079,"1,079 synaptic contacts among the 208 reconstructed neurons",,,Serial block-face SEM,,,,11,Max Planck Institute for Neurobiology of Behavior – caesar,Max Planck Institute for Biological Intelligence,DE,hybrid,10.1038/s41592-022-01621-0,peer-reviewed,Whole larval brain imaged at 14 x 14 x 25 nm; only a small share is reconstructed.
winding2023,Drosophila larva brain (Winding et al.),fly,Drosophila melanogaster,1st-instar larva,whole brain,2023,3013,neurons,544000,"544,000 synapses between the reconstructed neurons",,,Serial-section EM,,,,20,Howard Hughes Medical Institute,Howard Hughes Medical Institute,US,green,10.1126/science.add9330,peer-reviewed,
dorkenwald2024,"Fruit fly whole brain, FlyWire (Dorkenwald et al.)",fly,Drosophila melanogaster,adult female,whole brain,2024,139255,neurons,54500000,"54.5 million synapses between the neurons (""5 x 10^7 chemical synapses"" in the abstract)",,,Serial-section TEM,,,33,293,Princeton University,University of Würzburg,DE,hybrid,10.1038/s41586-024-07558-y,peer-reviewed,"Built on the 2018 FAFB electron microscopy volume of Zheng et al. (7,062 sections, about 40 nm)."
shapsoncoe2024,"Human cortex fragment, H01 (Shapson-Coe et al.)",human,Homo sapiens,surgical sample,1 mm3 of temporal-lobe cortex,2024,16000,neurons,133700000,133.7 million synaptic connections (automated),,1.0,Multibeam SEM,,1400,,31,Harvard University,Harvard University,US,green,10.1126/science.adk4858,peer-reviewed,"57,216 cells in the volume; about 16,000 are neurons. 104 cells manually proofread."
takemura2024,Fruit fly male nerve cord (Takemura et al.),fly,Drosophila melanogaster,adult male,ventral nerve cord,2024,23000,neurons,,10 million T-bars and 74 million postsynaptic densities (no single synapse count),,,FIB-SEM,,,,84,Howard Hughes Medical Institute,Howard Hughes Medical Institute,US,gold,10.7554/eLife.97769,peer-reviewed,Numbers read in the 2023 bioRxiv version; the eLife text was not available to us.
vishwanathan2024,Larval zebrafish brainstem (Vishwanathan et al.),zebrafish,Danio rerio,larva,brainstem block (250 x 120 x 80 micrometres),2024,3000,neurons,,not stated as a count in the text read,,0.0024,Serial-section EM,,,,31,Princeton University,Princeton University,US,hybrid,10.1038/s41593-024-01784-3,peer-reviewed,Volume = 250 x 120 x 80 cubic micrometres = 0.0024 mm3 (our arithmetic).
bates2025,"Fruit fly brain + nerve cord, BANC (Bates et al.)",fly,Drosophila melanogaster,adult female,brain and ventral nerve cord,2025,,neurons,,"the text gives ""10^8 synaptic connections"" for the fly, not for this dataset",,,,,,,116,Harvard University,Boston Children's Hospital,US,hybrid,10.1101/2025.07.31.667571,preprint,"Expected ~160,000 neurons in the dataset; no reconstructed count in the text, so none recorded."
microns2025,"Mouse visual cortex, MICrONS (MICrONS Consortium)",mouse,Mus musculus,mouse,about 1 mm3 of visual cortex,2025,82247,neurons,524000000,524 million synaptic clefts detected (automated),,1.0,Serial-section TEM,,2000,,96,Princeton University,Allen Institute for Brain Science,US,hybrid,10.1038/s41586-025-08790-w,peer-reviewed,"82,247 neurons were detected in the larger of two sub-volumes by an automated model; only a subset is proofread. Raw data ""2 Pb"" as printed."
nern2025,Fruit fly optic lobe (Nern et al.),fly,Drosophila melanogaster,adult male,right optic lobe,2025,53000,neurons,,about 49 million connections in the optic lobe neuropils (not synapses),49000000,,FIB-SEM,,,,71,Howard Hughes Medical Institute,Howard Hughes Medical Institute,US,hybrid,10.1038/s41586-025-08746-0,peer-reviewed,
verasztoe2025,"Platynereis larva, whole body (Veraszto et al.)",other,Platynereis dumerilii (marine worm larva),3-day larva,whole body,2025,2675,cells,26881,"26,881 synapses inside the connectome graph (32,381 identified); 2,675 graph nodes incl. 467 fragments and non-neuronal cells; 9,162 cells with a soma in the volume",,,Serial-section TEM,,,,7,Heidelberg University,Heidelberg University,DE,gold,10.7554/eLife.97964,peer-reviewed,"eLife reviewed preprint 2024, version of record 2025."
xie2025,"Larval zebrafish whole brain, Fish-X (Xie et al.)",zebrafish,Danio rerio,6-day larva,"whole brain, retina and anterior spinal cord",2025,176810,cells,25250000,25.25 million synapses found by whole-brain algorithmic reconstruction (preprint),,,Serial-section EM,,,,39,Chinese Academy of Sciences,Chinese Academy of Sciences,CN,green,10.1101/2025.06.12.659365,preprint,"bioRxiv preprint, licence CC BY-NC-ND: facts cited only. Algorithmic, not proofread; cells, not neurons."
berg2026,Fruit fly male CNS (Berg et al.),fly,Drosophila melanogaster,adult male,whole central nervous system (brain + nerve cord),2026,166700,neurons,,46 million presynapses connected to 312 million postsynaptic densities (preprint),,,FIB-SEM,160,,44,111,Howard Hughes Medical Institute,Howard Hughes Medical Institute,US,hybrid,10.1016/j.cell.2026.08.015,peer-reviewed,"Cell, 3 September 2026 (CC BY 4.0). Preprint text says 166,691 neurons; the published abstract says 166,700. A press aggregator reported ""125 million synapses"": not found in the paper or the Janelia page, not used."