ARTICLE IN BRIEF
Neurologists and neuroscientists comment on the opportunities and challenges posed by a new funding initiative from the DoD's Defense Advanced Research Projects Agency to support the development of a new generation of neural stimulation devices.
For many soldiers and military veterans, the burden of combat extends far beyond its visible wounds — as demonstrated by the growing number of veterans returning home with neuropsychiatric conditions, such as post-traumatic stress disorder, anxiety disorders, and depression; and the high suicide rate in military personnel. Last month, responding to these alarming trends, the US Department of Defense (DoD) announced a new $70 million, five-year neuroscience and neurotechnology initiative to improve the brain health of military troops and veterans.
The project, called the Systems-Based Neurotechnology for Emerging Therapies (SUBNETS) program, will be led by DoD's Defense Advanced Research Projects Agency (DARPA) as a part of the BRAIN initiative announced by President Obama earlier this year. (For more on the BRAIN initiative, see “A $100 Million Brain Research Initiative Gets the Presidential Nod”: http://bit.ly/14NXez0.)
The program hopes to encourage research into a new generation of devices, inspired by deep brain stimulation (DBS), that incorporate near real-time recording, analysis and stimulation of neural systems. DARPA has set a lofty goal — developing a device ready for Food and Drug Administration review within five years.
The focus for SUBNETS will be post-traumatic stress disorder, major depression, borderline personality disorder, general anxiety disorder, traumatic brain injury, substance abuse/addiction, and fibromyalgia/chronic pain.
Justin Sanchez, PhD, DARPA program manager and neural engineer, told Neurology Today that DBS has already made a clinical impact on more than 100,000 people, but “there is still a great burden of psychiatric and neurologic disease that remains unaddressed.” This project “seeks to leverage, but move beyond DBS and today's limited understanding of complex-systems-based disease to create new interventions,” which are based on insights from the intersection of neuroscience, neurotechnology, and clinical therapy.
Neurologists, Dr. Sanchez said, have a significant role to play in what will ideally be a multidisciplinary collaboration with psychiatrists, neurosurgeons, neural engineers, microelectronic engineers, neuroscientists, statisticians and mathematicians, with representatives from academia, government, and industry.
The first solicitation for research proposals for SUBNETS is available here: http://1.usa.gov/1bwdZBA.
Commenting on the funding initiative, neurologists told Neurology Today they were excited by DARPA's announcement of SUBNETS and what it could mean for advancing research into brain networks and improving neurotechnology. Mahlon DeLong, MD, professor of neurology at the Emory Clinic in Atlanta and one of the pioneering neurologists involved in deep brain stimulation, told Neurology Today that SUBNETS is “very timely.” The project “appropriately targets human patients — not just basic research — and I think that's where we are in this field,” he said.
Agreeing, Jordan Grafman, PhD, director of brain injury research and chief of the cognitive neuroscience laboratory at the Rehabilitation Institute of Chicago, told Neurology Today “surely we can learn from those [planarian or fruit flies] studies, but there are unique aspects to human behavior and for human disease that really can't be easily mimicked by studying those species, and it's not clear that there will be any direct connection between basic research on those types of species and humans.”
Still, more basic science research is needed to understand the key brain networks involved in different aspects of daily function, as well as those specifically involved in the traumatic injuries and disorders that DARPA hopes to target, he said. Dr. Grafman has published extensively on brain imaging in patients with traumatic brain injury and neuropsychological conditions.
Additionally, he said, to build on the present knowledge from DBS studies and develop the kinds of brain implants DARPA describes, will require better studies of brain signal patterns. Among the research questions: “Can we be more precise about identifying the functional significance of brain-evoked signal patterns? Can we abstract ongoing brain signals in order to permit not only precise motor movements, but other aspects of behavior as well? I think all of that is a long-term goal of this project.”
Although research to expand the use of DBS to various neurologic and psychiatric conditions continues to evolve, Dr. DeLong pointed out that “the actual technology has not changed that much.” This new project, he believes, can accelerate that part of the process. Also, he said, “the ability to collect information while you stimulate is a big advance, and may open other opportunities.”
But is five years enough time? Dr. DeLong told Neurology Today, “I'm always skeptical of these time frames, but it's good to have a goal; it makes everybody work harder.” The key here, he said, is “bringing together different disciplines. We really need to have combined experience and collaboration with engineering, physiology, neurology, psychiatry in order to pull this off.”
Hopefully, Dr. Grafman said, this initiative will provide an incentive for individuals who don't ordinarily do this type of research — particularly engineers — to become interested in neuroscience.
For certain neuropsychiatric disorders, said Dr. Grafman, where you can localize the prominent dysfunction to a specific region of the brain, there may be a role for “an artificial implant of some kind that you can turn on and off, like DBS for Parkinson's.” However, with moderate to severe traumatic brain injury, where you have widespread damage to the brain, “it's going to be a much more challenging task to utilize an implant-like device to aid somebody in a meaningful way, whereas the idea of augmentation, or using attachable wearable devices, might be more useful.”
Dr. Grafman said that he looks forward to seeing the experimental methods and procedures used to test out the new technologies. Regardless of the “success” of the project, as a result of this effort, Dr. Grafman said, we are going to improve our knowledge of neural networks within the brain, as well as the regional responsibilities and how those brain regions contribute to the broader brain network as a whole.
DARPA has a historical tradition of taking risks, he said, “only a small number of which pan out, but when they pan out, they tend to be spectacular; as opposed to the standard way of doing science, which — while it may be successful — is often slow and plodding.” Dr. Grafman added that he hopes SUBNETS will also include high-risk research projects, with high-reward potential.
LINK UP FOR MORE INFORMATION:
•. DARPA announcement of SUBNETS initiative: darpa.mil/NewsEvents/Releases/2013/10/25.aspx© 2013 American Academy of Neurology
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