A new nerve-cell monitor will help those studying brains

SCIENCE is a mixture of the intellectual and the practical. And the practical requires tools. Until the invention of the telescope, astronomy had been stuck in a rut for millennia. Until the invention of the microscope, microbiology did not exist. Neuroscience, too, has advanced recently on the back of some powerful tools, particularly techniques for scanning whole brains. But the devices that look at the nitty-gritty of how nerve cells themselves work are still Heath-Robinson affairs. These are...