A helicopter is a rather complicated craft to fly--it doesn't really glide, and moves by controlling the pitch and power of its rotor blades. Imagine what it would take for a helicopter to fly by mind control.

But it's the brain's motor cortex, and not necessarily centers for imagination, that were proven to navigate an unmanned model helicopter. Bin He, a biomedical engineer at the University of Minnesota, reported in the Journal of Neural Engineering that by hooking up electrodes to a volunteer's head, the signals from the volunteer's brain could fly a helicopter (at least a small one).

The research indicates how robotic prosthetic limbs could be improved to incorporate more signals from the brain, creating more realistic body-like motions. Currently, robotic prosthetics are surgically attached to nerve endings and tissue in the remaining limbs of patients, limiting the use of such devices to people who have had severed limbs and are otherwise severely disabled.

Aircraft have been flown via mind control before, but He's study was more sophisticated. The volunteer's brain activity was able to make the helicopter fly up, down, left and right, and could follow precise aerial courses. This added a key extra dimension to previous work.

By imagining that he was clenching his right or left fist, or both, the "pilot" sent messages from the motor cortex of the brain that were picked up by an electroencephalogram, or EEG. These messages, transmitted as waves over the EEG, were specific enough to turn the helicopter left or right, up (imagining both fists clenched) or down.

It wasn't exactly easy to find pilots for the craft. Trainees were put through a number of exercises which started by moving a cursor on a computer screen. Not everybody passed. He believes that some people could not create the precise focus needed to make clear commands to the aircraft through the motor cortex (He has, in fact, found that people who have honed their focusing skills through meditation or yoga were better at controlling computer cursors in this way).

By making a non-invasive control from the brain to any device (not just a helicopter), it would be possible to make precisely functioning non-invasive medical devices.