Nobel Prize in Physiology or Medicine 2026: Karl Deisseroth, Peter Hegemann and Georg Nagel win for optogenetics

Scientists Karl Deisseroth, Peter Hegemann and Georg Nagel have jointly won the 2026 Nobel Prize in Physiology or Medicine for their discoveries concerning light-gated ion channels and optogenetics, the Nobel Assembly at Karolinska Institutet announced on Monday.

The trio was recognised for research that made it possible to use light to control the activity of individual nerve cells. The breakthrough has transformed neuroscience by allowing researchers to switch specific neurons on or off in living brains and study how neural circuits influence memories, feelings and behaviour.

What is optogenetics?

Optogenetics combines light with genetic techniques to control nerve cells with high precision. The breakthrough began with research by Peter Hegemann and Georg Nagel on Chlamydomonas, a single-celled alga. They discovered channelrhodopsin, a light-sensitive protein that forms a channel through which charged ions can flow when exposed to blue light.

Karl Deisseroth subsequently introduced the gene responsible for channelrhodopsin into nerve cells. By shining blue light on these modified cells, he was able to trigger nerve signals. He published the breakthrough in 2005 and later demonstrated that the technique could control nerve cells in the brains of living mice.

The technique, now known as optogenetics, has become an important tool in neuroscience laboratories around the world. Researchers use it to investigate neural circuits linked to specific memories, emotions and behaviours, including those relevant to neurological and psychiatric disorders. Researchers are also studying potential clinical applications, including efforts to restore sight in people with visual impairment.

Deisseroth, 54, is associated with Stanford University in the United States, while Hegemann, 71, is based at Humboldt University in Berlin and Nagel, 73, is at the University of Würzburg in Germany. The three laureates will share the Nobel prize money of 12 million Swedish kronor, approximately $1.2 million.

The Physiology or Medicine prize traditionally opens Nobel Week. The announcements for Physics, Chemistry, Literature and Peace will follow through the week, with the Nobel Memorial Prize in Economic Sciences scheduled for October 12.