Mind Over Machine From: Popular Science - 02/2004 By: Carl Zimmer The Defense Advanced Research Projects Agency (DARPA) has invested heavily in brain-machine interface research, whose promised benefits include thought-controlled robots for military operations and mentally-directed artificial limbs for paralysis victims. Such projects build upon research which established that the electrical impulses of neurons are similar to the on-off digital code of computers, which resulted in the theory that cracking the code could lead to machines operated by mental command. Miguel Nicolelis of Duke University and John Chapin of the State University of New York Downstate Health Science Center conducted pioneering research which revealed that analyzing the signals from a relatively small group of neurons via implanted electrodes produces enough data to recognize many different mental commands, thus removing a major impediment to brain-machine interface development. At Duke, Nicolelis implanted electrodes into primates and trained them to operate a robot arm by watching a cursor on a computer screen and making it move with a joystick; through the electrode link, the computer learned to decode the animals' brain patterns and translate them into cursor movements so that the monkeys could be weaned off the joystick and taught to control the prosthetic limb by thought alone. The Duke researchers must increase the system's portability and unobtrusiveness to make it practical for human quadriplegics. They believe this can be achieved with implanted neural electrodes attached to a processor that wirelessly transmits thoughts to a portable computer that in turn relays those commands to the prosthesis; Chapin is working on a force-feedback system to help users more precisely control limbs. DARPA, which funds the Duke research, is also supporting a University of Michigan project into mind-controlled robots in the hopes that such devices can be used for reconnaissance missions in dangerous environments. Former director of DARPA's Brain-Machine Interface Program Alan Rudolph notes that a viable interface for soldiers will require a noninvasive method for reading brain inputs. http://www.popsci.com/popsci/medicine/article/0,12543,576464,00.html --- Brain-Machine Interface Building on earlier studies in which monkeys learned to control a robot arm using only their brain signals, researchers at Duke University Medical Center have conducted their first human studies of the feasibility of using brain signals to operate external devices. They have shown that arrays of electrodes can provide useable signals for controlling such devices, and are currently working to develop prototypes that enable paralyzed people to operate "neuroprosthetic" and other external devices. To relieve a patient's symptoms of Parkinson's disease and tremor disorders, surgical procedures are routinely conducted that involve implanting electrodes into the brain and then stimulating it with small electrical currents. During these surgeries, the researchers recorded the electrical signals from arrays of 32 microelectrodes. The patients are awake during surgery, and while brain signals were being recorded, the volunteer patients were asked to play a hand- controlled video game. Reseachers found that the signals contained enough information to be useful in predicting the hand motions - a requisite for reliably using neural signals to control external devices. For the complete story, visit http://link.abpi.net/l.php?20040405A2