The Blu-Ray Rat
[...] Scientists are genetically engineering neurons to respond to a wavelength of laser light similar to that used in hi-def players. So far, they've used this mind-control beam to remotely control lab rats.
The key is making brain cells sensitive to light. Stanford neuro engineer Karl Deisseroth does it by using a virus to insert a gene from green algae into the motor cortex, the part of the brain that controls voluntary movement. The gene makes a photosensitive protein. When Deisseroth delivers a flash of blue light via a fiber-optic cable... neurons with the protein fire off signals to their neighbors. If he times the pulses right, Deisseroth can make the rat's whiskers move. Because rodents rely on their feelers to sense objects around them, that seems to affect their navigation. [...]
