JUDY WOODRUFF: For decades, researchers have worked to create a better and more direct connection between a human brain and a computer to improve the lives of people who are paralyzed or have severe limb weakness from diseases like ALS.
Those advances have been notable, but now the work is yielding groundbreaking results.
Special correspondent Cat Wise has the story.
It’s part of our Breakthroughs reporting and for our weekly segment about the Leading Edge of science and technology.
CAT WISE: Dennis Degray is a 64-year-old quadriplegic who is writing a sentence on the computer screen in front of him using only his brain.
A former volunteer firefighter, Degray had a bad fall 10 years ago which severed his spinal cord. As part of an early stage clinical research study led by Stanford University, Degray and two other volunteer participants with ALS had small sensors implanted in their brains in an area called the motor cortex, which controls movement.
Even though Degray can no longer physically move his arms, the neurons in that part of his brain, and in the brains of many other paralyzed individuals, remain active.
The sensors in his brain listen in to those neurons, which emit different electrical signals depending on the direction Degray thinks about moving his hand.
DENNIS DEGRAY, Clinical Research Participant: To move the pointer around, I imagine a ball lying on a table and with my hand lying on the ball. And as I roll the ball forward, the pointer goes up, and as I roll the ball back toward me, the pointer goes down, and, of course, left and right correspondingly.
CAT WISE: The neural signals are transmitted to the computer through two devices that screw into small pieces of equipment called pedestals protruding from Degray’s scalp. In the computer, sophisticated algorithms turn the movements in his mind into cursor movements on the screen.
DENNIS DEGRAY: It’s very liberating. To be able to utilize a portion of my body that has not worked to actually cause and effect is great fun, just great fun.
DR. JAIMIE HENDERSON, Stanford University: If you had asked me five years ago if I thought I would see these types of systems becoming available any time within my lifetime, I would have been pretty skeptical.
But I would say now that, within the next 10 years or so, we will probably begin to see systems that can restore function to people with paralysis.
CAT WISE: Dr. Jaimie Henderson is a professor of neurosurgery at Stanford University. He implanted the sensors in Degray’s brain, and he is one of the leaders of a scientific team from several universities around the country working on the technology called BrainGate.
DR. JAIMIE HENDERSON: The principles by which we’re reading out brain signals are well-established.
The research advance is using the computer algorithms to figure out what the brain is doing, an operating system that can read out signals on millisecond time scales and feed that back to the user, so that they can be in very tight feedback loop with the machine and use it more efficiently.
CAT WISE: That improved efficiency in the BrainGate operating system, which has been in development for more than a decade, is at the heart of a new research paper Dr. Henderson and his colleagues released.
The study, which was funded in part by the National Institutes of Health, also a “NewsHour” funder, highlighted the typing results of Degray and the two others in the study.
DR. JAIMIE HENDERSON: Our participants in this study were able to type at anywhere between 20 to up to almost 40 correct characters per minute, which translates to somewhere between four and eight words per minute, which is the fastest typing now demonstrated in people with paralysis by a factor of anywhere from two to four.
This allows you to type at speeds that are now approaching what you can use on a cell phone.
CAT WISE: Surveys of those with paralysis show that speed of communication is important to them. That’s one of the frustrations with current systems that track eye and face movements.
One of the goals of the research now is evaluate the safety of brain-computer interfaces, but there are still a lot of questions and concerns about connecting brains to computers. It’s a debate the Stanford team embraces.
KRISHNA SHENOY, Stanford University: Over the past few decades, we have become increasingly comfortable with having various devices implanted in our bodies.
CAT WISE: Study co-author Krishna Shenoy says his broader research with neural prosthetics shows people are comfortable with much more now than just knee replacements, for example, electrodes to control Parkinson’s tremors.
KRISHNA SHENOY: Fifteen years ago, society started to become comfortable with deep brain stimulators. When you turn the system on, the tremor essentially stops. It’s like magic. Tens of thousands of people are walking around every day with these electronic systems in their brains.
So, the question is, is there something sacrosanct about the brain, that we shouldn’t go there? This is extremely important to be guided by bioethics, neuroethics. And this is a case where we can do tremendous good if this is developed and deployed correctly.
CAT WISE: Dennis Degray says that, while he’s able to utilize a range of communication systems, he’s participating in the trial to help advance a technology that may benefit those who don’t have as many options.
DENNIS DEGRAY: What we’re performing here is basic science. We’re building a foundation upon which the roboticists, the communicators, the mechanical engineers, medical prosthetic device manufacturers, all of them will be able to utilize the controls that we are learning about at this point.
DR. JAIMIE HENDERSON: We have, I think, made slow, but steady progress, and are getting to the point where we can now really imagine systems that can be fully implanted, wireless, able to be used 24 hours a day without calibration.
I think we’re still a ways away from that, but we’re getting closer.
CAT WISE: The Stanford research team hopes to enroll another trial participant in the next year or two. And they are now exploring ways to connect people and their brains to new devices.
For the PBS NewsHour, I’m Cat Wise in Palo Alto, California.
JUDY WOODRUFF: Fascinating.