The 2026 Nobel Prize in Medicine
The 2026 Nobel Prize in Physiology or Medicine was awarded on Monday to Karl Deisseroth, Peter Hegemann and Georg Nagel for their discoveries concerning light-activated ion channels and optogenetics, a method that enables individual nerve cells in a living brain to be activated or deactivated. The Nobel Assembly at the Karolinska Institute in Stockholm announced the prize, noting that the three scientists are based at universities in Germany and the United States. Deisseroth, 54, works at Stanford University in California; Hegemann, 71, at Humboldt University in Berlin; and Nagel, 73, at the University of Würzburg in Germany.[S1][S2][S3][S4][S5][S6][S7][S8]
The committee said the discoveries had laid the foundations of a new era in neuroscience. In a statement, it explained that optogenetics is now used in laboratories around the world to reveal the mysteries of the brain. The Nobel Assembly emphasised that the method has radically transformed understanding of the brain and that new findings emerge daily, helping to address one of humanity's great mysteries: how the brain works. The prize money this year amounts to 12 million Swedish kronor, equivalent to about 1.2 million dollars.[S1][S2][S3][S4][S5][S6]
From an alga to a tool for neuroscience
The work began in the early 2000s, when Hegemann and Nagel discovered channelrhodopsin, a protein found on the surface of Chlamydomonas, a single-celled alga that swims towards light. When illuminated with blue light, the protein opens a channel through which charged ions flow into the cell, generating an electrical impulse. Hegemann had wondered how Chlamydomonas could swim towards a light source. The two researchers found that the protein made cells sensitive to light regardless of the cell type into which it was introduced.[S1][S2][S3][S4][S6]
Deisseroth then turned channelrhodopsin into a light-controlled switch for nerve cells. He introduced the channelrhodopsin gene into rat neurons and, by illuminating the cells with blue light, managed to trigger a nerve signal, a breakthrough he published in 2005. Two years later, he succeeded in making the light-controlled switch for neurons work in the brains of living mice. This development gave rise to optogenetics, which combines genetic and optical techniques to control the activity of specific neurons with great precision.[S1][S2][S3][S4][S6]
What optogenetics has revealed about the brain
Using optogenetics, researchers have been able to reveal the neural circuits that control memories, emotions and specific behaviours related to neurological and psychiatric disorders. The technique allows scientists to observe what happens when particular neural circuits are switched on or off. It has been used to study circuits linked to memory, emotions and behaviour, as well as mechanisms involved in conditions such as Parkinson's disease, epilepsy and depression. There are also investigations into using it to restore visual function in people with visual impairment.[S1][S2][S3][S4][S6]
The committee highlighted that optogenetics has transformed the way the brain is studied. According to the Nobel Assembly, the method is now employed in laboratories worldwide to uncover the brain's mysteries. The president of the Nobel Committee for Physiology or Medicine, Per Svenningsson, remarked that the technique allows the brain to be mapped in ways previously only dreamed of. The prize announcement is followed by the awards for Physics on Tuesday, Chemistry on Wednesday and Literature on Thursday; the Peace Prize will be announced on Friday, and the Sveriges Riksbank Prize in Economic Sciences in Memory of Alfred Nobel on 12 October.[S1][S2][S3][S4][S5][S6]
