3 scientists win Nobel Prize in medicine for work unraveling the brain’s mysteries

STOCKHOLM — Three scientists won the 2026 Nobel Prize in physiology or medicine Monday for discoveries that allow researchers to switch on and off nerve cells in the living brain. Karl Deisseroth, a 54-year-old American, Peter Hegemann, a 71-year-old German, and Georg Nagel, a 73-year-old German, were selected by the Nobel Assembly of Sweden’s Karolinska Institute medical university and receive a prize sum amounting to 12 million Swedish crowns ($1.2 million), which is shared if there are multiple winners. Optogenetics “makes it possible to switch on, or off, the activity of individual nerve cells in a living brain,” the prize-givers said. “This method is now being used in laboratories around the world to reveal the brain’s mysteries.” The physiology or medicine prize traditionally opens the annual Nobel announcements, with awards in physics, chemistry, literature, peace and economics to follow over the coming days. The five original Nobel Prizes were created under the terms of Swedish inventor and industrialist Alfred Nobel‘s will and have been awarded since 1901, with only limited interruptions, chiefly during World War I and World War II. A sixth award, the economics prize, was established in 1968 by Sweden’s central bank, the Riksbank. The medicine prize has honored some of the most influential scientific discoveries of the past century, including Alexander Fleming’s work on penicillin, recognized in 1945, and Karl Landsteiner, who won in 1930 for his discovery of human blood groups. Last year, American scientists Mary Brunkow and Fred Ramsdell and Japan’s Shimon Sakaguchi won the prize for work shedding light on how the immune system spares healthy cells, creating openings for possible new treatments of diseases such as cancer. Nobel laureates are chosen by expert committees appointed by the prize-awarding institutions. The awards are presented in Stockholm, with the exception of the Peace Prize, which is handed out in Oslo, a tradition often linked to the union that bound Sweden and Norway during Nobel‘s lifetime. More than 125 years after Nobel signed his will, the prizes retain many of their long-standing traditions. The celebrations culminate Dec. 10, the anniversary of Nobel‘s death, when laureates receive their awards in ceremonies attended by Sweden’s and Norway’s royal families and are feted at gala banquets held in their honor.