Scientists win 2026 Nobel Prize for controlling brain cells with light

A discovery in tiny algae led to a Nobel Prize-winning breakthrough that allows scientists to switch brain cells on and off using light. The revolutionary technique has already helped researchers activate memories and is opening new possibilities for restoring vision and treating brain disorders. Scientists win 2026 Nobel Prize for controlling brain cells with light.

Karl Deisseroth, Peter Hegemann and Georg Nagel were honored for their research into “light-gated ion channels and optogenetics.” Peter Hegemann, at Humboldt University of Berlin, and Georg Nagel, at the University of Würzburg, wanted to understand how a tiny, single-celled alga called Chlamydomonas senses light. Light-sensing is not unique to animals with eyes: organisms throughout the living world use light to detect their surroundings and respond to changes in their environment. Even single-cell organisms have proteins that respond to light.

These proteins are used to move towards or away from light, to generate energy and to respond to the various demands of a 24-hour day. Hegemann and Nagel discovered that Chlamydomonas has a beautifully ingenious mechanism of light detection that relies on a single protein called channelrhodopsin. Channelrhodopsin is built into the outer membrane of the algal cell.