Karl Deisseroth of the United States and German scientists Peter Hegemann and Georg Nagel have received the 2026 Nobel Prize in Physiology or Medicine for discoveries that made optogenetics possible: the use of light to control selected nerve cells.

Both accounts trace the advance to channelrhodopsin, a light-sensitive protein found in single-celled algae by Hegemann and Nagel. Deisseroth then adapted it into a light-operated switch in neurons, showing that blue light could trigger a nerve signal in genetically modified rat cells and later work in living mouse brains. The Nobel Assembly described the result as a method that shows how nerve cells shape “memories, feelings and behaviours in the living brain.”¹

The Brazil Right coverage puts particular emphasis on the practical pathway from basic research to medicine. It notes that optogenetics has helped identify neural circuits tied to memory, emotions and behaviours associated with neurological and psychiatric conditions, and says researchers are exploring the method to restore vision for people with visual impairments. It presents the award as the foundation of “a new era in neuroscience.”¹

The Brazil Left account similarly calls the work revolutionary, but gives more weight to optogenetics as a widely used laboratory tool. It says the approach has enabled researchers to reveal circuits governing memories, emotions and behaviours relevant to neurological and psychiatric disorders.² It also points to a longer-term prospect of treatments for conditions including Parkinson’s disease, epilepsy and sensory disorders, rather than suggesting those applications are already established.

In that sense, the accounts converge on the central achievement: precise light-based control has changed how scientists investigate the brain. Their distinction lies mainly in whether the story is told through optogenetics’ potential clinical applications or its present-day value in decoding neural circuitry.