This undated handout photo released on October 5, 2026 by the University of Wuerzburg shows German scientist Georg Nagel as he was awarded the Röntgenmedaille science prize. The Nobel medicine prize was awarded on October 5, 2026 to US psychiatrist and neurologist Karl Deisseroth and German scientists Peter Hegemann and Georg Nagel for their pioneering work in the field of optogenetics. Optogenetics involves controlling nerve signals with light, and helps researchers understand how specific cell types contribute to behaviours like learning, fear, addiction and movement. The trio were honoured "for their discovery of a molecular switch for nerve cells", the Nobel Assembly said. (Photo by Robert EMMERICH / Julius-Maximilians-Universität Würzburg / AFP via Getty Images) / RESTRICTED TO EDITORIAL USE - MANDATORY CREDIT "AFP PHOTO / Julius-Maximilians-Universität Würzburg /Robert EMMERICH" - HANDOUT - NO MARKETING NO ADVERTISING CAMPAIGNS - DISTRIBUTED AS A SERVICE TO CLIENTS