Karl Deisseroth, Peter Hegemann and Georg Nagel have been awarded the 2024 Nobel Prize in Physiology or Medicine for developing optogenetics, a technique that uses light to control brain cell activity and map neural circuits linked to memory, emotion and behavior.
Hegemann and Nagel discovered channelrhodopsin in the early 2000s, a protein from algae with light-sensitive properties. Deisseroth then showed how to use this protein to switch nerve cells on and off in mouse brains. The technique has allowed researchers to study individual neural pathways and their roles in neurological and psychiatric disorders.
The Nobel Committee said optogenetics "fundamentally altered our understanding of the brain" by revealing connections between specific neural circuits and behaviors, feelings and bodily functions that were previously difficult to study. Per Svenningsson, chair of the Nobel Committee, described the method as offering "opportunities for mapping the brain in a way that we could once only dream of."
The technology is already moving into clinical use. In ongoing trials for retinitis pigmentosa, a disease that destroys sight-sensing cells in the eye, researchers inserted the light-sensitive algal protein into damaged eye tissue. Patients wearing special glasses that emit light regained some vision when the protein activated. The committee said researchers have "taken the first steps" toward using optogenetics as a medical treatment.
Researchers are also using the technique to study how the nervous system interacts with cells in other areas of the body, including the heart and gut. The three laureates will share the 12 million Swedish kronor prize, equivalent to £900,000.