Scientists unveil smaller, more powerful brain-machine interface

March 23 (UPI) -- Researchers have developed a new brain-machine interface that allows the human brain to link directly with silicon-based technologies. The novel device is less intrusive and more powerful -- able to capture more detailed neural activity data -- than similar kinds of technology.

Scientists described the new device in the journal Science Advances.

"Nobody has taken these 2D silicon electronics and matched them to the three-dimensional architecture of the brain before," study co-author Abdulmalik Obaid, graduate student in materials science and engineering at Stanford University, said in a news release. "We had to throw out what we already know about conventional chip fabrication and design new processes to bring silicon electronics into the third dimension. And we had to do it in a way that could scale up easily."

The device features a bundle of extremely thin wires that are implanted into the brain. The tiny wires measure the electrical signals of different parts of the brain and relay the information to a silicon chip on the outside.

"Electrical activity is one of the highest-resolution ways of looking at brain activity," said co-author Nic Melosh, professor of materials science and engineering at Stanford. "With this microwire array, we can see what's happening on the single-neuron level."

Using mouse models, scientists successfully captured a range of brain signals using the brain-machine interface.

The authors of the new study wanted to incorporate silicon into their device because silicon technologies are so abundant. The inclusion could allow their device to be integrated with a variety of communication and data processing technologies.

"Silicon chips are so powerful and have an incredible ability to scale up," said Melosh. "Our array couples with that technology very simply. You can actually just take the chip, press it onto the exposed end of the bundle, and get the signals."

Because the wires are so delicate, scientists needed to bundle them in a biologically-safe polymer outside of the brain. The bottom half of the bundle is polymer-free, allowing the individual wires to be precisely directed into different parts of the brain.

"The design of this device is completely different from any existing high-density recording devices, and the shape, size, and density of the array can be simply varied during fabrication," said co-author Jun Ding, assistant professor of neurosurgery and neurology. "This means that we can simultaneously record different brain regions at different depths with virtually any 3D arrangement."

"If applied broadly, this technology will greatly excel our understanding of brain function in health and disease states," Ding said.

In the future, scientists suggest the technology could be used to bolster medical therapies, including prosthetics and speech assistance.