Mind control via laser is a reality, but so far has been used exclusively to make tiny worms wriggle and lay eggs (which they would be doing anyway). Scientific American reports, with no word on when this will be applicable to human subjects:
Scientists have come a step closer to gaining complete control over a mind, even if that mind belongs to a creature the size of a grain of sand. A team at Harvard University has built a computerized system to manipulate worms—making them start and stop, giving them the sensation of being touched, and even prompting them to lay eggs, as seen in the video above—by stimulating their neurons individually with laser light, all while the worms swim freely in a petri dish. The technology may help neuroscientists for the first time gain a complete understanding of the workings of an animal’s nervous system.
The worm in question, Caenorhabditis elegans, is one of the most extensively studied organisms in biology: researchers have completely mapped and classified its cells—each individual has exactly 1,031— including its 302 neurons and the 5,000 or so connections among them. But science still does not know exactly “how neurons work together in a network,” says Andrew Leifer, a graduate student in biophysics at Harvard, For example, how does the worm coordinate its 100 or so muscles to relax and contract in a wave pattern as the worm swims?
To find out, Leifer and his collaborators genetically engineered the one-millimeter-long nematode worm to make particular cells in its body sensitive to light, a technique called optogenetics, developed in recent years by Stanford University psychiatrist and bioengineer Karl Deisseroth. Because the worm’s body is transparent, sharply focused lasers, pointed with an accuracy of 30 microns, could turn on or suppress individual neurons with no need for electrodes or other invasive methods. Leifer placed a microscope on a custom-built stage to track the worm as it swam around in a dish. He also wrote software that analyzed the microscope’s images to locate the target neurons, and then pointed and fired the lasers accordingly—all at a rate of 50 frames per second.