Trio win Nobel prize for leap in optogenetics; how it unlocks brain's mysteries

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-gated ion channels and optogenetics”, a technique that allows scientists to control the activity of nerve cells using light.The Nobel Assembly at Karolinska Institutet said the three scientists had laid “the foundation of a new era in neuroscience”. Their work has enabled researchers to switch individual nerve cells on or off in living brains, helping them study how neural circuits control memories, feelings and behaviours.Peter Hegemann and Georg Nagel discovered channelrhodopsin-1 and channelrhodopsin-2, a light-sensitive protein found in the single-celled alga Chlamydomonas. When exposed to blue light, the protein opens a channel through the cell membrane, allowing positively charged ions to flow in and generate an electrical signal.Karl Deisseroth later transformed this discovery into a tool for controlling nerve cells.