Mind-controlling a robotic arm without an electrode stuck in the brain is possible, but it requires extremely sophisticated readings and translations of electroencephalography (EEG) signals, says Bin He, professor of biomedical engineering at the University of Minnesota (Minneapolis).

There are even significant challenges when electrodes are actually used for brain computer interface because they tend to not be very biocompatible, He says.

The electrical signals--mu rhythms--produced by a brain when a person is actually moving something measure approximately 1 microvolt. Conversely, the signals produced when someone is thinking about doing it without doing it--the signals mind-controlled medical devices would use--are much smaller, He said after his opening keynote speech Monday for the MD&M Minneapolis conference running October 28-30.

"Picture me taking this plastic cup, throwing it into the ocean with the waves going up and down, and trying to find it," He says.

Nevertheless, He has had some success. He showed video to conference attendees of a student wearing an EEG cap who was able to control the movement of a remote controlled helicopter.

Such advances would make mind-control available to a wider segment of the population, since otherwise healthy people would otherwise not volunteer to have electrodes stuck in their brains.

Use of implanted devices for the paralyzed or others in sore need of such functionality is another story. But He notes that researchers have found that neurons start to form themselves around the electrodes eventually distorting the signals.

Something needs to advance technologically with the electrodes, He says.

"If anyone of you can develop something like that, make it biocompatible for several months or several years, that would be big business. I assure you," He says.

Recent University of Chicago research suggests that mind control might be used not only to control movement of a device, but to even sense touch through a device.

Researchers at the Rehabilitation Institute of Chicago (RIC) have developed a mind-controlled prosthetic limb that can initiate various movements after its wearer thinks about them. "The bionic leg allows me to seamlessly walk up and down stairs and even reposition the prosthetic by thinking about the movement I want to perform," explained Zac Vawter, an amputee who is testing the bionic leg. "This is a huge milestone for me and for all leg amputees."

Roughly one year ago, Vawter, while wearing the mind-controlled limb, climbed the 103 flights of stairs of Chicago's Willis Tower.

Chris Newmarker is senior editor of MPMN and Qmed. Follow him on Twitter at @newmarker.