Mapping the half-billion connections that allow mice to see

Summary

After nine years of painstaking work, an international team of researchers on Wednesday published a precise map of the vision centers of a mouse brain, revealing the exquisite structures and functional systems of mammalian perception. To date, it is the largest and most detailed such rendering of neural circuits in a mammalian brain. The map promises to accelerate the study of normal brain function: seeing, storing and processing memories, navigating complex environments. As importantly, it will deepen the study of brain disorders in anatomical and physiological terms — that is, in terms of the wiring and the relationships between circuits and signals. That’s especially promising for disorders that may arise from atypical wiring, such as autism and schizophrenia. “The technologies developed by this project will give us our first chance to really identify some kind of abnormal pattern of connectivity that gives rise to a disorder,” said Princeton University’s Sebastian Seung, the Evnin Professor in Neuroscience and a professor of computer science, who co-led the project. The work was published in a raft of papers on April 9, comprising a special edition of the journal Nature. The researchers digitally disentangled hundreds of thousands of cells and around half a billion connections, then traced each of those cells’ myriad branches and created a full 3D reconstruction of a cubic millimeter of brain tissue, roughly the size of a coarse grain of sand. Image by Amy Sterling, Seung Lab, Princeton University Along with Seung’s Princeton team, the consortium was co-led by teams at Baylor College of Medicine and the Allen Institute for Brain Science. In total, more than 150 researchers from 22 institutions worked on the project. It was primarily funded by the U.S. Office of the Director of National Intelligence and the National Institutes of Health. NIH representatives have cited this work as foundational to the future of health, disease and disorder. The intelligence office...