96
PHVSICS OF THE IMPOSSIBLE
quadriplegic permanently paralyzed from the neck down, took only a
day to learn entirely new computerized skills. He can now change the
channels on his TV, adjust the volume, open and close a prosthetic
hand, draw a crude circle, move a computer cursor, play a video game,
and even read e-mail. He created quite a media sensation in the scientific community when he appeared on the cover of Nature magazine in
the summer of 2006.
The heart of Donoghue's BrainGate is a tiny silicon chip, just 4 millimeters wide, that contains one hundred tiny electrodes. The chip is
placed directly on top of the part of the brain where motor activity is
coordinated. The chip penetrates halfway into the brain's cortex,
which is about 2 millimeters thick. Gold wires carry the signals from
the silicon chip to an amplifier about the size of a cigar box. The signals are then sent into a computer about the size of a dishwasher. Signals are processed by special computer software, which can recognize
some of the patterns created by the brain and translate them into mechanical motions.
In the previous experiments with patients reading their own EEG
waves, the process of using biofeedback was slow and tedious. But
with a computer assisting a patient to identify specific thought patterns, the training process is cut down considerably. In his first training session Nagle was told to visualize moving his arm and hand to the
right and to the left, flexing his wrist, and then opening and closing his
fist. Donoghue was elated when he could actually see different neurons firing when Nagle imagined moving his arms and fingers. "To
me, it was just incredible because you could see brain cells changing
their activity. Then I knew that everything could go forward, that the
technology would actually work," he recalled.
(Donoghue has a personal reason for his passion for this exotic
form of mind-machine interface. As a child, he was confined to a
wheelchair because of a painful degenerative disease, so he felt firsthand the helplessness of losing his mobility.)
Donoghue has ambitious plans to make BrainGate an essential
tool for the medical profession. With advances in computer technology, his apparatus, now the size of a dishwasher, may eventually be-
PHVSICS OF THE IMPOSSIBLE
quadriplegic permanently paralyzed from the neck down, took only a
day to learn entirely new computerized skills. He can now change the
channels on his TV, adjust the volume, open and close a prosthetic
hand, draw a crude circle, move a computer cursor, play a video game,
and even read e-mail. He created quite a media sensation in the scientific community when he appeared on the cover of Nature magazine in
the summer of 2006.
The heart of Donoghue's BrainGate is a tiny silicon chip, just 4 millimeters wide, that contains one hundred tiny electrodes. The chip is
placed directly on top of the part of the brain where motor activity is
coordinated. The chip penetrates halfway into the brain's cortex,
which is about 2 millimeters thick. Gold wires carry the signals from
the silicon chip to an amplifier about the size of a cigar box. The signals are then sent into a computer about the size of a dishwasher. Signals are processed by special computer software, which can recognize
some of the patterns created by the brain and translate them into mechanical motions.
In the previous experiments with patients reading their own EEG
waves, the process of using biofeedback was slow and tedious. But
with a computer assisting a patient to identify specific thought patterns, the training process is cut down considerably. In his first training session Nagle was told to visualize moving his arm and hand to the
right and to the left, flexing his wrist, and then opening and closing his
fist. Donoghue was elated when he could actually see different neurons firing when Nagle imagined moving his arms and fingers. "To
me, it was just incredible because you could see brain cells changing
their activity. Then I knew that everything could go forward, that the
technology would actually work," he recalled.
(Donoghue has a personal reason for his passion for this exotic
form of mind-machine interface. As a child, he was confined to a
wheelchair because of a painful degenerative disease, so he felt firsthand the helplessness of losing his mobility.)
Donoghue has ambitious plans to make BrainGate an essential
tool for the medical profession. With advances in computer technology, his apparatus, now the size of a dishwasher, may eventually be-