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Roy Bakay and Philip Kennedy of Emory University have implanted two-electrode wireless implants into humans with ALS and those who had strokes in the brain stem. The implants were pieces of glass shaped like cones into which gold electrical contacts were glued. The cones were filled with a special tissue culture medium that attracts brain cells to grow toward the contacts. These implants allow individuals to move a computer cursor and to type very slowly using brain signals. Because it is wireless, no external cable is needed. However, because there are only two electrodes, a patient is limited to performing only simple tasks.

www.brownalumnimagazine.com

John Donoghue and Gerhard Friehs have become the first to implant a multi-electrode array into a human patient. After earlier studies on monkeys, Friehs implanted the electrode into 25 year old Matt Nagle's brain in June 2004. It took 3 weeks for Nagle to recover from the surgery but it was eventually discovered that the neurons in the motor cortex of the quadripeligic still were active. After hooking the implant up to a computer and training Nagle, it was seen that Nagle could play a computer game, operate a cursor, turn on and off a TV, and check his email by using only his thoughts. Nagle's implant is to be removed soon as the trial comes to an end, however, other human trials are in progress. With this latest development, Donoghue has jumped to the front of the competition.

http://www.ocf.berkeley.edu

Jonathan Wolpaw and Dennis McFarland of the New York State Department of Health have created an EEG skullcap that allows patients to move a cursor up and down and side to side through the use of thoughts. Although the cap eliminates the need for an invasive surgical procedure and the risks associated, the current problem facing this device is the issue of a low signal-to-noise ratio. Because of this, the device is limited to controlling a cursor and it is unlikely that it could perform more complex tasks like controlled muscle movement.

http://www.bbc.co.uk/radio4/science

Miguel Nicolelis of Duke University has used multi-electrode implants which allow monkeys to reach and grasp with a robotic arm through the use of only brain signals. Though he has not tested his device on humans yet, plans for human trials are set to begin in the near future. These trials will be focused on academic research.

http://www.neurobio.pitt.edu

Andrew Schwartz of the University of Pittsburgh has implanted multi-electrode arrays into monkeys allowing them to use a robotic arm to feed themselves through thoughts alone. Currently, he is examing neural recordings in monkeys to examine the cortical representation or perception and action, the cortical prosthetic control of arm movement, cortical prosthetic control of hand movement and the transformation between cortical and muscle activity.