Brain-computer interface begins new clinical trial for paralysis (6/11/2009)

Scientists at the Massachusetts General Hospital (MGH) have initiated the BrainGate2 pilot clinical trial to expand restorative neurotechnology research for some patients with paralysis. This trial expands on previous research that explores methods that may help paralyzed patients control assistive technologies.

The research, to be conducted jointly by physician researchers at MGH and neuroscientists and engineers at Brown University, has received approval from the hospital's Institutional Review Board (IRB) to begin recruiting patients. John Donoghue, PhD, of Brown and the Providence VA Medical Center, and Leigh Hochberg, MD, PhD, of MGH, Brown, the VA and Harvard Medical School are leading this research to evaluate how people with spinal cord injury, brainstem stroke, muscular dystrophy, amyotrophic lateral sclerosis (ALS), or limb loss may be able to use brain signals to control assistive devices.

"We are working to develop and test technologies that we hope will help patients with devastating illnesses that limit their ability to move or to speak," says Hochberg, a vascular and critical care neurologist at MGH, Brigham and Women's Hospital and Spaulding Rehabilitation Hospital. "The goal of our research is to harness the brain signals that ordinarily accompany movement and to translate those signals into actions on a computer, like moving a cursor on the screen, or the movement of a robotic or prosthetic limb."

Donoghue said the new trial is taking place at a time of great promise for neurotechnology research.

"We are entering a new age of neurotechnology," Donoghue says. "Our fundamental understanding of the nervous system, combined with advances in engineering may help people with brain and spinal cord injuries and diseases."

A previous clinical trial run by an outside company, Cyberkinetics, Inc., together with researchers at MGH and Brown, demonstrated that the neural signals associated with the intent to move a limb can be "decoded" by a computer in real-time and used to operate external devices. This device, called the BrainGate Neural Interface System, involved a sensor placed on a part of a study participant's brain called the motor cortex. During research sessions, a computer was connected to the sensor through a port on the participant's head, allowing participants to control a computer cursor by simply thinking about the movement of their own paralyzed hand. "We learned an incredible amount with the assistance of the first participants in the BrainGate trial, not only about how the motor cortex continues to work after paralyzing illness or injury, but also about how to harness these powerful intracortical signals for controlling computers and other assistive devices," Hochberg says.

For financial reasons, Cyberkinetics stopped funding the trial and withdrew itself from the research. The promising clinical trial continues, now based at Mass. General. A new academically-based Investigational Device Exemption (IDE) application, BrainGate2, was developed in 2008 to follow-up on research previously published in peer reviewed journals. The BrainGate2 pilot clinical trials will be directed by Dr. Hochberg at MGH with close collaboration with researchers at Brown University and the Providence VA Medical Center. BrainGate2 will expand on previous research, honing the hardware and software that decode the brain signals that are causing the cursor to move on a screen.

This IDE is part of a larger research effort, the ultimate goals of which include "turning thought into action": developing point and click capabilities on a computer screen, controlling a prosthetic limb and a robotic arm, controlling functional electrical stimulation (FES) of nerves disconnected from the brain due to paralysis, and further expanding the neuroscience underlying the field of intracortical neurotechnology. The research is focused not only on the ability to operate a computer, but also to assist people with ALS, spinal cord injury and stroke to control over their environment.

"Through ongoing development and testing, it is hoped that these technologies will eventually help to improve the communication, mobility and independence of people with severe paralysis," says Dr. Hochberg.

People with these types of paralysis have at least two characteristics in common: a brain that wants to direct movement and a body that fails to respond accordingly. Beyond the current clinical trial, the goal of the BrainGate research effort is to someday be able to provide a new pathway for brain signals to control external devices such as computers, or even one's own limbs that had been "disconnected" from the brain due to paralysis.

Note: This story has been adapted from a news release issued by the Massachusetts General Hospital

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