This animal study used Drosophila knockout lines to examine whether visual (Rh1) versus non-visual (Rh7) opsins contribute to blue-light-associated neural damage. Flies were continuously exposed to 488 nm blue light from egg deposition to 20 days, and brain DNA damage and vacuolisation were assessed. The study reports greater DNA damage and neurodegeneration markers in Rh1 knockout flies than in wild-type or Rh7 knockout flies, and concludes Rh1 is a predominant mediator of blue-light-induced neurotoxicity in the fly CNS.