The Nobel Prize in Physiology or Medicine was awarded on Monday to American Karl Deisseroth and Germans Peter Hegemann and Jörg Nagel, in recognition of their groundbreaking research in the field of optogenetics, which has radically transformed the understanding of the brain. The Nobel Committee in Stockholm announced that discoveries related to light-activated ion channels open therapeutic horizons for neurological and sensory disorders such as Parkinson's disease and epilepsy, allowing researchers to control individual neural circuits using light.
On Monday, the Nobel Committee in Stockholm announced the awarding of the 2026 Nobel Prize in Physiology or Medicine to American Karl Deisseroth and Germans Peter Hegemann and Jörg Nagel, honoring their research in optogenetics, marking the start of the prestigious award season.
The winners of the Nobel Prize in Physiology or Medicine, awarded by the Nobel Association at the Karolinska Institute in Sweden, receive a reward of 11 million Swedish kronor (1.2 million US dollars), in addition to a gold medal presented by the King of Sweden.
The committee explained that the prize was awarded "in recognition of their discoveries related to light-activated ion channels and the science of optogenetics."
This field helps researchers understand how specific types of cells contribute to behaviors such as learning, fear, addiction, and movement, and may someday lead to the development of treatments for neurological and sensory disorders, such as Parkinson's disease and epilepsy.
The Nobel Committee stated, "Using optogenetics technology, researchers have been able to uncover the neural circuits that control specific memories, emotions, and behaviors related to neurological and psychological disorders."
In clinical medicine, researchers are using this method in attempts to restore vision in individuals with visual impairments.
The committee added, "Optogenetics has brought about a radical change in our understanding of the brain. Every day brings new discoveries that help solve one of humanity's greatest mysteries: how our amazing brain works." By using light, researchers have become able to activate or deactivate individual neural circuits in the brain.
Groundbreaking discoveries in optogenetics
In the early 2000s, scientists Hegemann and Nagel were studying why a single-celled alga is capable of swimming toward a light source. They discovered a unique algal protein known as "channelrhodopsin," which exists on the cell surface.
When exposed to blue light, a channel opens through it, allowing charged ions to flow into the cell, generating an electrical impulse. They found that any cell into which this protein is introduced becomes light-sensitive. Deisseroth then introduced the gene responsible for producing the channelrhodopsin protein into neurons taken from rats.
By shining blue light on these cells, he was able to stimulate a neural signal. Deisseroth published his pioneering findings in 2005, and two years later, he succeeded in activating this light-control switch in neurons within the brains of living mice.
In 2021, both Deisseroth and Hegemann won the Lasker Award in recognition of their work in this field, an award often regarded as a precursor to the Nobel Prize.
The careers of the three winners
Deisseroth (54) serves as a professor at Stanford University in the United States, while Hegemann (71) is a professor of neuroscience at Humboldt University in Berlin. Nagel (73) is a professor of biophysics at the University of Würzburg.
The Nobel Prize in Physics is scheduled to be announced on Tuesday, followed by the Nobel Prize in Chemistry on Wednesday, and then the Nobel Prize in Literature on Thursday.
Some observers have speculated that the Swedish Academy might choose a female writer for this year's literature prize, possibly from Central or Latin America, after last year's award was given to Hungarian writer László Krasznahorkai. In this context, literary critic Lina Kalmetig told Agence France-Presse that Argentine writer Samantha Schweblin (48) might be among the potential candidates for this selection.
The Nobel Peace Prize, set to be announced on Friday, may be the most anticipated and intriguing, as it is the only Nobel Prize awarded in the Norwegian capital Oslo instead of Stockholm.
Some experts believe that the committee may choose a universally supported winner this year, following the controversy surrounding last year's award to Venezuelan opposition figure María Corina Machado.
Trump watches the Peace Prize
Last year, U.S. President Donald Trump exerted intense pressure to receive the prize, to the point that Machado ended up gifting him her Nobel medal.
The committee is aware that Trump is closely monitoring the prize this year as well. Nobel Committee secretary Christian Berg Hårvik said in an interview with Agence France-Presse, "There is always a lot of pressure, and perhaps attempts to exert pressure on the committee eventually," adding, "We are completely used to that."
Among the potential winners this year, there is speculation about jointly awarding the prize to both the organization "Save the Children" and Mykola Kulyba, a Ukrainian children's rights activist leading a campaign for the return of Ukrainian children illegally taken to Russia from the Russian-occupied Ukrainian territories.
The list also includes "Emergency Rooms" in Sudan, a vast network of volunteers risking their lives to help residents against the dual threat of war and hunger, as well as the "Committee to Protect Journalists" (CPJ), following the highest death toll year in the profession’s history in 2025. The Nobel Prizes will conclude with the announcement of the Nobel Prize in Economics on October 12.