American Karl Deisseroth and Germans Peter Hegemann and Georg Nagel won the 2026 Nobel Prize in Physiology or Medicine on Monday (October 5) for their discoveries on light and optogenetics that have helped understand how the brain works.

The Nobel Assembly of Sweden’s Karolinska Institute medical university said Deisseroth, 54, Hegemann, 71, and Nagel, 73, were selected for their \.