Imagine being able to turn on and off specific brain cells with a ray of light. This was science fiction before, but today it is the most potent tool in neuroscience. The research leading to this breakthrough has brought Karl Deisseroth, Peter Hegemann, and Georg Nagel the 2026 Nobel Prize in Physiology or Medicine.
The innovation they pioneered is called optogenetics – a combination of genetics and light that allows switching specific neurons on and off. Rather than just observing which part of the brain is turned on or off, scientists can activate or deactivate specific cells and see what would happen.
