presented by Caltech
Our ability to move depends on our spinal cord transmitting signals between
our brain and limbs.
That's why severe spinal cord injuries often result in paralysis.
Neural prosthetics facilitate movement via
artificial limbs. Tiny electrodes implanted in the motor cortex
transmit signals to a computer where they are translated as instructions for
robotic arm.
But because the motor cortex is concerned with the mechanics of movement
it signals often result and slow jerky motions.
Take drinking from a cup: if we had to think through
every detail - bending the elbow, rotating the arm -
the action would be lurching instead have smooth.
At Caltech, researchers and Professor Richard
Andersen's lab, working in partnership with Keck Medicine of USC
and Rancho Los Amigos National Rehabilitation Center,
wanted the robotic arm to produce more fluid gestures.
So, they turned their attention to the posterior parietal cortex,
or PPC, the region and the brain involved in movement planning
rather than movement execution - what you intend to do
rather than are the steps it takes for you to do.
This area, as we suspected is involved in
the planning movements and so it's almost like a set
of basic types movement
on then the brain can go in and configure those to form
complex kinds movement. But it actually reflects
the high-level intent of the subject.
So it's rather fascinating because
it's not a part of the brain that actually controls
the muscles so much
as the plans that you make to do something.
First the implanted a neuroprosthesis in the PPC of a paralyzed patient.
Then they asked him to visualize specific actions.
His neurons fired, sending instructions to the robotic arm
Using only his thoughts, he was able to guide the arm to shake hands
and even play "rock, paper, scissors,"using swift, fluid motions.
So, when we implanted the subject, still
was in an area of the brain that had never been implanted
that had really never been researched and so
it was entirely new territory.
So it was quite satisfying
to see that we could actually get signals out
use the signals, and use them in the way we hoped to.
Incredibly, the researchers also discovered
the patient can control activity of single brain cells
through imagining specific actions.
If he imagined a particular kind of movement, then he could easily control the cell
and so it was just searching for the right movement that he could imagine
to activate it. And that was really amazing.
So, we can say, "On, off,"
and he can just turn it on, turn it off. You can say, "Imagine moving your shoulder."
and it will fire.
For different have different neurons, they'll have different particular properties. "Imagine moving your wrist."
It won't.
It's so amazing because he can't move,
but he always could imagine moving.
So we can tap into that
imagination of movement. Researchers hope to use these findings to develop devices that
help paralyzed patients with everyday tasks, such as drinking from a cup
or brushing teeth.
to learn more about this and other groundbreaking research from Caltech,
visit caltech.edu