Overview
- The male connectome, which was published Sept. 3, 2026, and released as an open dataset, charts the entire central nervous system — brain, optic lobes and ventral nerve cord — totaling roughly 166,700 neurons and millions of synapses.
- Researchers built the map by slicing tissue and imaging it with focused ion beam–scanning electron microscopy, assembling the images with machine learning and validating results through extensive human proofreading that the team says equaled 44 years of labor.
- Direct comparison with the 2024 female connectome shows several hundred sex-specific cell types that make up about 4.8% of male neurons and 2.4% of female neurons, and finds roughly 9% of male neurons participate in connections that differ between sexes.
- Three companion studies use the map to trace taste pathways, map visual processing that extends deep into the brain, and identify a male-specific network tied to courtship and aggression, showing how identical sensory inputs can be routed to different behaviors.
- Investigators present the project as both an immediate tool for experiments — enabling precise targeting of neurons and circuit tests — and a technical roadmap for scaling connectomics to small vertebrates and, over many years, larger mammalian brains.