To be a functional member of society, being able to communicate is very important. If a person can get their message across, whether by speaking or by some other means, it will facilitate their life. Sadly, some people who suffer from paralysis can not. They are fully conscious and aware of their surroundings, but trapped inside a paralyzed body, not only unable to move but also unable to communicate in any way.
There is, however, a new technology called Brain-computer interface (BCI) which enables people with paralysis to control off the shelf tablet devices just by thinking about making cursor movements and clicks. Think of it like a mind-controlled mouse. BCI translates a participant’s brain activity into commands that a computer can understand. The research team that is evolving this science suggests that people who lose their capacity to speak may be able to continue to communicate with this technology.
The study is led by the BrainGate consortium, a collaboration of scientists, engineers and physicians from Brown University’s Carney Institute for Brain Science, the Providence Veterans Affairs Medical Center (PVAMC), Massachusetts General Hospital (MGH) and Stanford University.
“For years, the BrainGate collaboration has been working to develop the neuroscience and neuroengineering know-how to enable people who have lost motor abilities to control external devices just by thinking about the movement of their own arm or hand,” said Dr. Jaimie Henderson, a senior author of the paper and a Stanford University neurosurgeon. “In this study, we’ve harnessed that know-how to restore people’s ability to control the exact same everyday technologies they were using before the onset of their illnesses. It was wonderful to see the participants express themselves or just find a song they want to hear.”
How The Interface Works
The investigational BrainGate BCI includes a baby aspirin-sized implant that detects the signals associated with intended movements produced in the brain’s motor cortex. Those signals are then decoded and routed to external devices. A similar system has already proven successful in enabling people to move robotic arms or to regain control of their own limbs, despite having lost motor abilities from illness or injury.
About The Study
Three people with paralysis (tetraplegia) participated in the BrainGate clinical trial. Two of the participants had weakness or loss of movement of their arms and legs due to amyotrophic lateral sclerosis (ALS), a progressive disease affecting the nerves in the brain and spine that control movement. The third participant was paralyzed due to a spinal cord injury. All were enrolled to assess the safety and feasibility of the investigational BrainGate system. The process and results were published on November 21 in PLOS ONE.
Neural signals from the BrainGate BCI implant were routed to a Bluetooth interface that was configured to work as a wireless mouse. The virtual mouse was paired with an unmodified Google Nexus 9 tablet. Then, the participants were requested to perform a set of tasks. The tasks were designed to see how well the participants could navigate within (a variety of) commonly used apps, as well as the transition between the apps. Each one of the subjects performed seven tasks over three different days. Every task was accomplished within 15 to 30 minutes, successfully.
They were all able to navigate through commonly used tablet programs, including email, chat, music-streaming and video-sharing apps, all by just thinking about pointing and clicking a mouse. They had conversations with friends, shopped online, surfed the web, and much more.
The researchers were exceptionally pleased to witness the participants used the tablet interface to explore their hobbies and interests. One of the subjects, who was a former musician prior to the illness, played a snippet of Beethoven’s “Ode to Joy” on a digital piano interface.
“It was great to see our participants make their way through the tasks we asked them to perform, but the most gratifying and fun part of the study was when they just did what they wanted to do — using the apps that they liked for shopping, watching videos or just chatting with friends,” said lead author Dr. Paul Nuyujukian, a bioengineer at Stanford. “One of the participants told us at the beginning of the trial that one of the things she really wanted to do was play music again. So to see her play on a digital keyboard was fantastic.”
The fact that the tablet devices were entirely unaltered and had all preloaded accessibility software turned off was an important part of the study: “The assistive technologies that are available today, while they’re important and useful, are all inherently limited in terms of either the speed of use they enable, or the flexibility of the interface,” said Krishna Shenoy, a senior author of the paper and an electrical engineer and neuroscientist at Stanford University and Howard Hughes Medical Institute. “That’s largely because of the limited input signals that are available. With the richness of the input from the BCI, we were able to just buy two tablets on Amazon, turn on Bluetooth and the participants could use them with our investigational BrainGate system right out of the box.”
On average, the participants were able to make up to 22 point-and-click selections per minute while using a variety of apps. In text apps, they were able to type up to 30 effective characters per minute.
The subjects report that the interface was quite intuitive. “The tablet became second nature to me,” reported one research subject in the study. “It felt more natural than the times I remember using a mouse.”
The study also has the potential to open important new lines of communication between patients with severe neurological deficits and their health care providers: “This has great potential for restoring reliable, rapid and rich communication for somebody with locked-in syndrome who is unable to speak,” said Jose Albites Sanabria, who performed this research as a graduate student in biomedical engineering at Brown University. “That not only could provide increased interaction with their family and friends, but can provide a conduit for more thoroughly describing ongoing health issues with caregivers.”
“When I see somebody in the neuro-intensive care unit who has had an acute stroke and has lost the ability to move or communicate, I’d like to be able to say, ‘I’m very sorry this has happened, but we can restore your ability to use the technologies you were using before this happened, and you’ll be able to use them again tomorrow,’” Hochberg said. “And we are getting closer to being able to tell someone who has been diagnosed with ALS, ‘even while we continue to seek out a cure, you will never lose the ability to communicate.’ This work is a step toward those goals.”