This quick TED talk entry is courtesy of TED.com. Ed Boyden shows how, by inserting genes for light-sensitive proteins into brain cells, he can selectively activate or de-activate specific neurons with fiber-optic implants. With this unprecedented level of control, he’s managed to cure mice of analogs of PTSD and certain forms of blindness. On the horizon: neural prosthetics. Session host Juan Enriquez leads a brief post-talk Q&A.