Brain research at Brown

Brain implants that record or stimulate neural activity to help people with nervous system damage will be made possible under a new US National Institutes of Health grant awarded to Brown University.

The National Institute of Biomedical Imaging and Bioengineering and the National Institute of Child Health and Human Development awarded the five-year, $6.5m grant to Brown, which will coordinate research with partners from Cyberkinetics and the Cleveland FES Center.

The university-industry team will develop a ‘microsystem-on-a-chip’, a neural interface that is thin, flexible and about as big as an adhesive bandage. Unlike any other neural interface, the new system will be fully implantable and will communicate wirelessly. Information from the brain will be transmitted through the skin in a digital data streaming technique similar to high-speed optical telecommunications. That digitised data can be used to control assistive devices, such as computers or wheelchairs, which bring independence to people with paralysis.

‘This grant will take neural interfaces to the next level,’ said John Donoghue, a Brown neuroscientist and the chief scientific officer at Cyberkinetics. ‘The devices that come out of this project will bring us much closer to our goal of helping people who can’t move or who struggle to communicate because of central nervous system injuries or disorders.’

Arto Nurmikko, a Brown professor of engineering and physics, will lead the team developing the new silicon-encapsulated system, which will consist of a sensor and signal processor at one end and a high-speed signal transmitter and power source at the other. In one version, the system will send a stream of digital data down a fibre optic cable under the skin that leads to a pacemaker-sized power and processing unit in the chest. This unit will provide a strong, stable optical signal that can be used as a command source to control wheelchairs, prosthetic limbs, or other devices.

This new technology will also provide a wireless sensor for BrainGate, the system that turns the brain’s electrical signals into movement commands. BrainGate has allowed people with paralysis to operate a computer in order to read e-mail, control a wheelchair and operate a robotic hand in Food and Drug Administration (FDA) approved pilot trials overseen by Cyberkinetics. Brown faculty and students created the Foxborough, Massachusetts, company based on research and technology developed in the Donoghue laboratory.

Currently, BrainGate involves a sensor implanted in the brain, a connector that protrudes through the scalp and a cable that extends from the connector, carrying the brain’s signals out of the body to a set of computer processors that translate those signals into movement commands. The new system will be much smaller and sit under the skin.

The new technology could have applications beyond the control of assistive devices. Brain signals recorded and decoded by the device could be used to detect and predict epileptic seizures. Or the system might be used to treat disorders ranging from depression to Parkinson’s disease.

The research funding will allow the scientists to test the new wireless system – already a prototype in the Nurmikko lab – in a human patient with paralysis of all four limbs.

The grant will also allow scientists to develop a similar microsystem that stimulates, rather than records, brain activity. This technology would eventually allow for feedback that restores touch perception to people with paralysis or other nervous system damage.

The group is also planning to couple its wireless neural interface to a functional electrical stimulation (

FES

) system, which uses electrical impulses to trigger muscle and limb movement. Such a system would recreate the normal path from brain to muscles using physical components, allowing people with paralysis to make simple movements under direct brain control that could potentially be used to perform tasks such as eating or drinking.