Brown neurosurgeon Gerhard Friehs performed Nagle’s implant operation at Rhode Island Hospital in Providence in June 2004. Friehs is an expert at implanting neuro-devices such as the Activa brain stimulators for Parkinson’s patients that control the muscle tremors associated with the disease. On a plastic model, Friehs showed me the spot where he drilled a small hole into Nagle’s skull, above the region that controls the left arm. Friehs then inserted the implant using a pneumatic inserter, a device he says is like a staple gun that shoots the electrode array onto the brain.
Nagle was first put under general anesthesia, though Friehs says that in the future, this may not be necessary. Technicians then used magnetic-resonance imaging (MRI) of Nagle’s brain to pinpoint the motor cortex area specific to his anatomy. In the operating room, Friehs used the MRI data to guide him to the precise coördinates in Nagle’s brain and then revved up a high-speed drill to remove a half-dollar-sized circle of skull. Friehs inserted the four-by-four-millimeter electrode chip, the wires, and the pedestal and replaced the piece of skull. Total operating time: about four hours.
Six weeks later, after Nagle’s wounds had healed and the immediate threat of infection was past, the researchers prepared to test Braingate. Cyberkinetics technician Abraham Caplan, who makes the house calls with Saleh to operate Braingate two or three times a week at the assisted-living center where Nagle lives, remembers the first time they plugged in Nagle, in August 2004. On the video of this inaugural experiment, Nagle is sitting in his chair, and Saleh asks him to imagine moving his hand to the left. The computer broadcasts the snaps and pops of the signals that race across its screen, as it reads the brain’s real-time chatter, which it correctly translates into a cursor moving left on Nagle’s screen. “Not bad, man,” says Nagle, “not bad.”
Soon after, Nagle was able, with practice, to draw a crude circle on the screen with his mind, and he progressed to playing Pong and learning to move the cursor to click commands that control his television, turning it on and off, changing the stations, and adjusting the volume. “It’s like riding a bicycle,” says Donoghue. “At first he’s wobbly, he oversteers, and then he’s suddenly riding.” Nagle can talk and operate the computer at the same time, just as a healthy person might sing a song and walk. “This is important, because he doesn’t need to actively think of moving his hands to the left or right,” says Donoghue. “He just thinks about moving the cursor, and it moves.”
To understand what Braingate means for Nagle, I visit Leigh Hochberg, the Harvard neurologist. Hochberg, who is a consultant at the Spaulding Rehabilitation Hospital in Boston, works with patients who have suffered strokes or severe spinal-cord injuries. He shows me the Assisted Technology Group’s room at Spaulding, where quadriplegic and other severely disabled patients come to operate computers and other machines using devices hooked up to eyelids or lips or tongues, whatever they can still move. For those with no muscle movement, special cameras track pupil motion, which patients have learned to control in order to operate cursors. Others inhale and exhale through a straw to move a wheelchair.
Hochberg is the chief investigator for the Cyberkinetics FDA trial at Spaulding; this was the second site chosen for the trial, after Sargent Rehabilitation Center in Warwick, RI, the base for Nagle’s trial. Hochberg and coinvestigator Joel Stein, Spaulding’s medical director for the stroke program, have begun recruiting patients to fill the spaces allowed under the FDA license. Surgenor also wants to open another clinical-trial site, possibly in the Midwest. This will become even more important if the FDA approves human Phase II trials, which would involve up to several dozen patients.
“I think in the short term we’re not looking for a cure for spinal-cord injury,” says Stein, who nevertheless believes that in the long term Braingate will prove useful for patients with certain types of motor injuries. “We don’t want to oversell this to our patients, but the potential in the future is great.”