The brain's wiring had hidden pinch points all along

For decades, textbooks described the tree-like branches of brain cells — the dendrites that receive signals — as smooth cables. An international team led by researchers at the University Hospital of Bonn has now shown that picture is incomplete: using advanced microscopy, they found tiny, previously overlooked pinch points along the dendrites of both mouse and human brain cells, only a few hundred nanometers wide. Published in Science Advances, the discovery could change how we understand learning and memory, since a cell branch's shape governs how it passes signals.