A new method to record brain activity accurately at scale has been developed by researchers at London’s Francis Crick Institute, Stanford University, and University College London. The technique could lead to new medical devices to help amputees, people with paralysis, and people with neurological conditions such as motor neurone disease.

Research in mice developed an accurate, scalable method to record brain activity across large areas, including on the surface and in deeper regions simultaneously. This technology provides the basis for future developments beyond neuroscience research.

Using the latest in electronics and engineering techniques, the new device combines silicon chip technology with super-slim microwires – up to 15 times thinner than a human hair. The wires are so thin they can be placed deep in the brain without causing significant damage. Alongside its ability to accurately monitor brain activity, the device could also be used to inject electrical signals into precise areas of the brain.

“This technology provides the basis for lots of exciting future developments beyond neuroscience research. It could lead to tech that can pass a signal from the brain to a machine, for example, helping those with amputations to control a prosthetic limb to shake a hand or stand up. It could also be used to create electrical signals in the brain when neurons are damaged and aren’t firing themselves, such as in motor neurone disease,” says Andreas Schaefer, group leader in the neurophysiology of behavior laboratory at the Crick and professor of neuroscience at UCL.

When the device is connected to a brain, electrical signals from active neurons travel up the nearby microwires to a silicon chip, where the data is processed and analyzed, showing which areas of the brain are active.

The design of the device allows it to be easily scaled, depending on the size of the animal, with a few hundred wires for a mouse to more than 100,000 for larger mammals. This is a key feature of the device as it means it holds the potential to be scaled for use with humans.