Pentagon spurs new work on a brain implant to aid memory problems
DARPA's Restoring Active Memory program will attempt to develop implantable technology to bridge gaps in the injured brain and restore normal memory function to people with memory loss caused by injury or disease.
But the Pentagon is betting tens of millions of dollars that so-called neuroprosthetics will someday be used by victims of traumatic brain injuries and other conditions to overcome memory problems.
Its first beneficiaries may be wounded warriors. But if the effort succeeds, healthy people too may one day clamor for implantable brain gear that can turbocharge human cognition.
The Defense Advanced Research Projects Agency announced this week that it has contracted with the University of California, Los Angeles and the University of Pennsylvania to lead a four-year effort to develop such a device. Teams of scientists from the two institutions will be aided by neural technology experts at California’s Lawrence Livermore National Lab, and by a pair of giants in the design and manufacture of brain-stimulating devices, Medtronic Inc. and Neuropace Inc.
“This is just not cocktail party talk,” Geoffrey Ling, director of DARPA’s biological technologies office, said in a conference call with reporters. “We have so much hope that this new program is going to do wonderful things to restore our injured service members,” he said.
The research program, known as Restoring Active Memory, will focus on declarative memory — the ability to record and recall times, places and other facts necessary for daily living. Although the program is driven by the need to help service members who suffered traumatic brain injuries — often the result of roadside bombs used in the recent wars — the first human test subjects will be people with memory difficulties caused by epilepsy.
The Restoring Active Memory initiative extends the efforts of a burgeoning field that is exploring the potential of “brain-machine interfaces” to compensate for injury, illness or disability — and one day, perhaps, to enhance human performance. Just as cochlear implants bypass faulty auditory nerves to allow hearing in the deaf, new technologies and better understanding of the central nervous system are allowing scientists to test devices that reroute motor commands around severed spinal cords and cause muscles in the legs and arms to move.
But building an actual memory aid for the forgetful will be an even more daunting task, said Satinderpall Pannu, project leader at Lawrence Livermore Labs. “The first challenge is understanding how memory really works,” he said — a process scientists are just beginning to nail down.
For that, researchers at UCLA and University of Pennsylvania will rely on an army of healthy volunteers willing to perform memory tasks while their brains are imaged and recorded. And they will turn to a group of patients who already have some experience with neural implants.
Electronic devices are already implanted in the brains of tens of thousands of people with Parkinson’s disease and epilepsy. For those with Parkinson’s, deep brain stimulator devices are implanted in regions of the brain that control movement, to tame such symptoms as tremors, stiffness, slowed speech and walking problems. A much smaller population of patients with seizure disorders that don’t respond to medications have devices implanted in a wide range of brain regions to monitor seizure activity and short-circuit the electrical storms that disrupt their functioning.
A UCLA research team led by Dr. Itzkah Fried, a neurosurgeon, will collect data from epilepsy patients that use such devices with the aim of developing a model of memory formation that could be used to test a wireless memory device.
All of those subjects will help investigators map the widespread pattern of neural activity and pinpoint the exact clusters of brain cells that fire — or misfire — when we make, store and retrieve memories.
“We don’t have the Rosetta Stone for the memory system,” said Michael J. Kahana, director of University of Pennsylvania’s computational memory lab and a lead investigator on the project. “The DARPA project is trying to dramatically accelerate that effort to decipher that Rosetta Stone. We’re poised to do it. With this multisite effort, we might just be able to pull it off.”
The information gleaned will in turn guide the design of devices much more advanced than brain stimulators now in use. Starting as early as 2017, the Pentagon initiative aims to build and test in humans at least two devices. They would sense and interpret signaling in the brain associated with normal, healthy memory formation, then use that information to bridge gaps in the neural circuitry to restore or improve memory formation and recall.
The UCLA team will focus on a part of the brain known as the entorhinal area, an important gateway to the hippocampus, where memories are formed and stored. Fried’s research has shown that stimulating the entorhinal area enhances memory.
UCLA will receive up to $15 million over the next four years, with funding dependent on progress.
The University of Pennsylvania team is to receive $22.5 million over the next four years. There, scientists from a wide range of disciplines are exploring the contributions that other parts of the brain contribute to memory, including the frontal, temporal and parietal cortices.
“Memory depends on the interplay between activity in widespread brain areas,” where memories take on context and meaning, and are embellished with sensory and emotional dimensions, Kahana said. “Memory is about weaving together all those myriad experiences and tagging them with geotags and time tags so that you can find them again when you want them.”