Let there be light

New technology illuminates neuronal conversations in the brain

In the beginning, the brain was a dark and shapeless void.

LET THERE BE LIGHT Neurons (illustrated) made to produce certain proteins can be activated by light. Pasieka/Science Photo Library/Getty Images
PROTEIN POWER Optogeneticists use the light-activated protein channelrhodopsin-2, made by Chlamydomonas reinhardtii (shown).