A technique that enables scientists to control the behaviour of cells using flashes of light has been named Method of the Year 2010 by the journal Nature Methods. Optogenetics, as it’s called, has already been used by neuroscientists to show which nerve cells fire when a sleeping mouse wakes. The technique is also expected to shine light on the interactions of proteins inside cells.

This video explains how optogenetics works and shows how it’s been used to control behaviour in mice, worms and flies.