Medicine 2026 · Announced Oct 5
Karl Deisseroth
A brain doctor who found a way to turn single kinds of brain cells on and off with light.
Born 1971 in Boston · United States · Stanford University
Their part in the prize
Two German scientists found a protein in pond algae that opens when light hits it. Deisseroth's lab took that protein and put it into nerve cells. Then they flashed blue light. The cells fired, right on cue.
That turned a strange algae fact into a tool. The tool is called optogenetics. It lets a lab pick one kind of brain cell and switch it on or off.
Why they went after it
He is a psychiatrist. That is a doctor for illnesses of the mind. He wanted to know which brain cells go wrong in his patients. No tool could tell him. So he helped build one.
Why it matters
Before this, nobody could test what one type of brain cell does in a living animal. Now labs everywhere use it to study sleep, fear, memory and movement. In 2021 it gave a blind man back a small amount of sight.
More to know
- He still treats patients.
- In 2013 his lab showed CLARITY, a way to make a whole brain see-through.
- He wrote a book for everyone, Projections, about the patients who shaped his thinking.
The long road
- 1971Born in Boston.
- 2000Finishes a science doctorate and a medical degree at Stanford.
- 2004Opens his own lab at Stanford.
- 2005The breakthrough. His lab fires nerve cells with flashes of light.
- 2013Shows CLARITY, the see-through brain method.
- 2016Wins the Breakthrough Prize in Life Sciences.
- 2018Wins the Kyoto Prize.
- 2021Shares the Lasker Award with Peter Hegemann and Dieter Oesterhelt. Publishes Projections.
- 2026Nobel Prize in Physiology or Medicine.
Shared with
The official reason for all 3: "for their discoveries concerning light-gated ion channels and optogenetics"