Forget using clunky headsets and implants to control brain cells... one day, you might only need to use sound waves and some chemicals. Salk Institute scientists have found a way to control the brain cells of a tiny nematode worm through ultrasound. All they need to do to trigger activity is add a membrane ion channel to a neuron cell and blast it with ultrasonic waves -- in this experiment, the researchers changed the worm's direction through sound bursts. The approach is not only relatively unintrusive, but can reach deep into the body. You could trigger neural activity without ever hooking up an electrode, even for much larger animals.
This doesn't amount to total mind control, and it's not certain that this works with mammals yet. The Salk team has only just started testing with mice, and humans are a distant prospect. If it does work, though, it could prove a boon to medicine. Doctors could use ultrasound to selectively activate not only parts of the brain, but muscles and other places where cells will respond to ultrasound. They could stimulate unresponsive cells, correct irregular behavior and otherwise get your body's activity back on track.
[Image credit: De Agostini Picture Library]