Medicine 2026 · Announced Oct 5
They learned to switch brain cells on and off with light.
Shared by three people
In plain words
Some pond algae have a protein that opens when light hits it. Hegemann and Nagel found it and showed how it works. Deisseroth put it into brain cells. Now a flash of light can turn one exact kind of brain cell on or off.
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.
The official reason
"for their discoveries concerning light-gated ion channels and optogenetics"
24
years from the first light-switch protein paper (2002) to the prize
The long road
- 2002Nagel and Hegemann describe the first light-gated channel from algae.
- 2003They describe a second, stronger one. It becomes the main tool.
- 2005The Deisseroth lab uses it to fire nerve cells with flashes of light.
- 2007Light is used to change the behavior of a moving mouse.
- 2021A blind patient regains partial sight in a first human test.
- 2026Nobel Prize in Physiology or Medicine.