Paralysed people might one day be able to operate smartphones and tablets just by thinking about the actions they want to perform, with help from sensors implanted in their brains, a recent experiment suggests.
While previous experiments have had some success using brain sensors paired with customized computers to help paralyzed patients type up to eight words a minute, the current test focused on making it possible for these patients to use tablets and smartphones right out of the box without any special modifications, said lead author Dr. Jaimie Henderson of the Stanford University School of Medicine in California.
“We are still likely a number of years away from having a fully implantable, FDA-approved device that would be available for widespread use,” Henderson said by email. “However, I’m convinced that most of the technological hurdles have been solved and that we will one day in the near future see assistive devices that allow people with paralysis to control a computer using only their thoughts.”
The current experiment included just three patients. Two of them had weakness or loss of movement of their arms and legs due to amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig’s disease; a third patient was paralyzed from a spinal cord injury.
For the experiment, scientists implanted devices the size of a baby aspirin into the motor cortex, the area of the brain involved in planning and executing voluntary movements.
The implant was designed to detect signals associated with intended movements and then transmit these signals to a Bluetooth interface configured to work like a wireless mouse. The virtual mouse was paired to an off-the-shelf Google Nexus 9 tablet.
With the sensor and the wireless “mouse,” participants were able to navigate through commonly used tablet programs, including email, chat, music-streaming and video-sharing apps.
They also messaged with family, friends, members of the research team and their fellow participants. And, they surfed the web, checked the weather and shopped online.
One participant, a musician, played a snippet of Beethoven’s “Ode to Joy” on a digital piano interface.
Participants were able to make up to 22 point-and-click selections per minute while using a variety of apps, researchers report in PLoS ONE.
In text apps, the participants were able to type up to 30 effective characters per minute using standard email and text interfaces.
The research was done by the BrainGate consortium, a team of doctors, scientists and engineers who are working on products to restore independence to individuals with paralysis and neurologic diseases.
BrainGate members and other research groups have previously shown that the device in the current study can enable people to move robotic arms or regain control of their own limbs, despite having lost motor control due to injury or illness, the study authors note.
“For a little less than two decades, researchers have been developing brain-computer interface (BCI) systems to restore lost function (such as communication and movement) to persons living with chronic paralysis,” said A. Bolu Ajiboye of Case Western Reserve University in Cleveland, Ohio.
“These systems capture the natural activities of the brain, and allow users to command and operate usually specialized devices by direct modulation of brain activity (i.e. just by thinking),” Ajiboye said by email. Ajiboye has worked with BrainGate but wasn’t involved in the current experiment.
The unique aspect of the current project is that it doesn’t require customized tablets and can work with the same products consumers without paralysis might buy, said Steven Chase, co-director of the program in neural computation at Carnegie Mellon University in Pittsburgh, Pennsylvania.
“What’s new here is the rather elegant demonstration that patients can control an unmodified computer tablet and interact with all the common software programs that these devices have: email, web browsers, chat programs, etc.,” Chase, who wasn’t involved in the experiment, said by email. “This means that specialized software won’t have to be designed for users of these devices, which greatly expands the range of applications these patients would immediately have access to.”