Light switches for brain cells win 2026 Nobel Prize

According to the Nobel Assembly at Karolinska Institutet, the scientists were jointly honored “for their discoveries concerning light-gated ion channels and optogenetics.”

Deisseroth represents the Howard Hughes Medical Institute and Stanford University in the United States, while Hegemann and Nagel work at Germany’s Humboldt University of Berlin and the University of Würzburg, respectively.

“Optogenetics provides opportunities for mapping the brain in a way that we could once only dream of,” said Per Svenningsson, Chair of the Nobel Committee for Physiology or Medicine.

The discoveries began with Hegemann’s interest in how a single-celled alga, Chlamydomonas, swims toward light. In the early 2000s, he and Nagel identified channelrhodopsin, a protein on the alga’s cell surface that opens a channel when exposed to blue light. Charged ions then flow into the cell, generating an electrical impulse.

The researchers found that introducing the protein into other cells also made them sensitive to light.

Deisseroth subsequently introduced the gene for channelrhodopsin into rat nerve cells and used blue light to trigger nerve signals. He published the breakthrough in 2005 and, two years later, made the technique work in the brains of living mice.

Optogenetics is now used worldwide to study how nerve cells influence memory, emotions and behavior, helping scientists better understand neurological and psychiatric disorders. Researchers are also exploring whether the method can help restore sight.

Earlier, Qazinform News Agency reported that the Nobel Foundation had increased the 2026 prize amount to $1.22 million per category, marking the Nobel Prize’s 125th anniversary.