Karl Deisseroth, Peter Hegemann and Georg Nagel were awarded the 2026 Nobel Prize in Physiology or Medicine on Monday for discoveries involving light-gated ion channels and the development of optogenetics.
The technique allows researchers to switch particular groups of nerve cells on or off with light and observe the resulting changes in behavior. It has become a powerful tool for studying how neural circuits shape memory, emotions and other functions.
Experts discussing the award during Nobel Week at the University of Warsaw said the work was a striking example of basic research turning a mechanism found in nature into a way to study the brain.
Anna Malik of the Institute of Developmental Biology and Biomedical Sciences at the University of Warsaw’s Faculty of Biology explained that the work originated with light-sensitive proteins found in algae.
When exposed to light, the proteins trigger the movement of ions across a cell membrane, producing an electrical signal. Researchers found that by introducing similar proteins into selected neurons, they could then activate those cells with light.
“If we introduce such a protein into a particular group of neurons in a mouse brain, we can stimulate those cells with light and see what effect this has, for example, on the animal’s behavior,” Malik said.
The technique effectively gave researchers a targeted switch for individual groups of neurons, she added. It has helped scientists identify neural circuits involved in processes including fear responses, addiction and depression.
“That opens the way to further research on therapies,” Malik said.
Bartłomiej Kisiel of the Clinical Research Support Center at the Military Institute of Medicine – National Research Institute in Warsaw cautioned that neurons do not naturally respond to light in this way. In humans, light-sensitive receptors are normally found in the retina rather than the brain.
By inserting light-sensitive molecules into neurons, however, researchers can make those cells respond to light in laboratory animals. Kisiel said the method remains far from routine use in patients but offers researchers an unusually precise way to study how the brain works.
Jakub Drożak of the University of Warsaw’s Institute of Biochemistry said the prize also recognized the value of basic science.
The ion channels used by the laureates originally evolved to help algae detect light, he said. Scientists then adapted them into a tool for studying neurons and other cells.
“The knowledge we continue to gain using this tool will result in new therapies and, above all, a better understanding of the brain and the functioning of the nervous system,” Drożak said.
(rt/gs)
Source: IAR/PAP