The 'light switch' for brain cells wins the Nobel — and gave a blind patient partial sight

Karl Deisseroth, 54, of Stanford, Peter Hegemann, 71, of Humboldt University Berlin, and Georg Nagel, 73, of the University of Würzburg won the Nobel for optogenetics — light-gated ion channels. In the 1990s and 2000s, Hegemann and Nagel found channelrhodopsin in the single-celled pond alga Chlamydomonas; Deisseroth showed that neurons engineered with the gene could be switched on and off with light. In a 2021 trial, a blind retinitis-pigmentosa patient regained partial vision. The prize is 12 million Swedish kronor (about $1.2 million).