Peter Hegemann, Georg Nagel and Karl Deisseroth. On October 5, 2026, the Nobel Assembly at Karolinska Institutet awarded them the Nobel Prize in Physiology or Medicine for optogenetics, a method that uses light to control nerve cells and reveal how they shape memories, feelings and behaviours in the living brain.
In the early 2000s, Hegemann and Nagel discovered channelrhodopsin, a protein in the single-celled alga Chlamydomonas that opens an ion channel when hit by blue light. Deisseroth put the gene for that protein into rat nerve cells and showed in 2005 that blue light could trigger a nerve signal; two years later he made the technique work in the brains of living mice.
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