The Nobel Prize in Physiology or Medicine 2026 has been awarded to Karl Deisseroth, Peter Hegemann and Georg Nagel for their discoveries concerning light-gated ion channels and optogenetics.

The Nobel Assembly at the Karolinska Institute in Stockholm announced the winners on Monday, kicking off Nobel week.

Deisseroth, 54, is based at Stanford University in California and is also affiliated with the Howard Hughes Medical Institute. Hegemann, 71, is at Humboldt University in Berlin, and Nagel, 73, is at the University of Wurzburg in Germany.

The three scientists were recognised for their research into the mechanisms the brain uses to switch on or off the activity of individual nerve cells.

The Nobel committee described the method as one that "is now being used in laboratories around the world to reveal the brain's mysteries."

Thomas Perlmann, secretary of the medicine committee, said he was able to reach all three winners by phone on Monday.

The prize money this year is 12 million Swedish kronor, equivalent to approximately $1.2 million or 901,500 British pounds. The sum is shared among the laureates.

The 2026 award marks the 117th time the prize has been given. Of the 235 laureates, including the latest winners, only 14 have been women.

Last year, the prize went to three scientists researching the immune system.

The medicine prize is followed by the physics prize on Tuesday, chemistry on Wednesday and literature on Thursday. The peace prize will be announced on Friday, and the Nobel Memorial Prize in Economic Sciences on October 12.