Daan Brinks develops all-optical electrophysiology tools for neuroscience. His lab engineers genetically-encoded voltage indicators (GEVIs) and combines them with optogenetics to read out and control neural circuit activity. Key directions: (1) engineering bright, fast GEVIs with improved photostability and voltage sensitivity; (2) multiplexed all-optical neural circuit mapping; (3) identifying rare aggressive cancer cells using voltage-sensitive dyes. His voltage imaging approach represents cutting-edge biosensing at the intersection of photonics and neuroscience.