To achieve their “pathetic” accomplishment, which was published
in July in Cell
, researchers fed a brain chunk about as big as a grain of sand through a machine that sliced it vanishingly thin. That machine then stuck the slices to a plastic tape to create a sort of film reel of the chunk. A scanning electron microscope captured each frame digitally so researchers could use computers to trace what they saw. Then, focusing on an invisibly small, more manageable portion of their sample, they accounted for every cellular detail of each frame.