Most of us take movement and balance for granted, and it’s only when something goes wrong that we realise how complicated it is. In the early 1900s, an Oxford researcher called Charles Sherrington examined microscope slides of muscles, nerves, the spine and the brain and traced the connections between them. Using this box of slides, he built up a picture of how muscles are controlled. Some diseases can damage nerve cells and affect muscle control. Researchers today still use the basic principles established by Sherrington to investigate how to fix these problems.