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

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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