Stanford professor Karl Deisseroth spent hours fielding congratulatory calls after learning he had won the 2026 Nobel Prize in medicine. Then he asked for a break for a more ordinary task: making school lunches for his children, who were asleep in the family home in California.

Deisseroth, 54, shared this year’s prize with German researchers Peter Hegemann and Georg Nagel for their work on optogenetics, a field that combines light with genes to switch neurons on and off in living brains. The Nobel Assembly called him at 12:27 am Pacific time. He said he lost the ability to form words for about 30 seconds when the news sank in.

Nagel learned he had won while sitting on a terrace in the sun in Italy. Deisseroth, a professor of bioengineering and psychiatry, often works past midnight. An hour after the announcement, he told reporters that no real sleep had been achieved. The prize recognises a technique that has transformed neuroscience research.