Two monkeys with tiny sensors in their brains have learned to
control a mechanical arm with just their thoughts, using it to
reach for and grab food and even to adjust for the size and
stickiness of morsels when necessary, scientists reported on
Wednesday.via NY Times The new experiment goes a step further.
In it, the monkeys’ brains seem to have adopted the mechanical
appendage as their own, refining its movement as it interacted
with real objects in real time. The monkeys had their own arms
gently restrained while they learned to use the added one. In
the experiment, two macaques first used a joystick to gain a
feel for the arm, which had shoulder joints, an elbow and a
grasping claw with two mechanical fingers. Then, just beneath
the monkeys’ skulls, the scientists implanted a grid about the
size of a large freckle. It sat on the motor cortex, over a
patch of cells known to signal arm and hand movements. The grid
held 100 tiny electrodes, each connecting to a single neuron,
its wires running out of the bra