2026 Nobel Prize in Physiology or Medicine: Deisseroth, Hegemann, Nagel

The 2026 Nobel Prize in Physiology or Medicine was awarded jointly to Karl Deisseroth, Peter Hegemann and Georg Nagel for complementary discoveries that created optogenetics. Hegemann and Nagel identified and characterized channelrhodopsins - light-gated ion channels from green algae that open in response to specific wavelengths and allow ion flow across membranes. That molecular insight established that single proteins can convert light into electrical signals, revealing a new class of photoreceptors with straightforward biophysical properties suited for experimental control.

Karl Deisseroth translated those microbial proteins into a versatile toolkit for neuroscience by combining genetic targeting, optics and electrophysiology to activate or inhibit selected neurons with millisecond precision. This optogenetic approach made it possible to manipulate defined cell types in intact brains, demonstrating causal links between neural activity and behavior, mapping circuit function, and probing mechanisms of neuropsychiatric and neurological disorders. The work transformed experimental neurobiology and spawned translational pathways toward light-based interventions, with each laureate receiving an equal one‑third share of the prize.