Brain Interfaces Made of Silk
Gentler, softer electrodes wrap around the folds of the brain to take higher-resolution measurements.
>
Now a group of researchers is building biocompatible electronics on thin, flexible substrates. The group hopes to create neural interfaces that take higher-resolution measurements than what's available today without irritating or scarring brain tissue.
>
"A device like this would completely open up new avenues in all of neuroscience and clinical applications," says Gerwin Schalk, a researcher at the Wadsworth Center in Albany, NY, who is not affiliated with the silk electrode group. "What I foresee is placing a silk-based device all around the brain and getting a continuous image of brain function for weeks, months, or years, at high spatial and temporal resolution."
>
The silk electronics researchers say this is their next step, and one of the major promises of the technology. They've already demonstrated thin, flexible silicon transistor arrays built on silk, and tested them in animals--just not in the brain yet. Schwartz says other groups have recognized the importance of multiplexing and signal amplification, but have been working with rigid circuit boards that are not as biocompatible. Adding these active components would reduce the number of wires needed in these implants, which today require one wire per sensor. And active devices could respond to brain activity to provide electrical stimuli, or release drugs. (One of the collaborators on the silk project, David Kaplan at Tufts University, has demonstrated that silk devices implanted in the brain in small animals can deliver anti-epilepsy drugs.)
Adding transistors to the electronics is currently a design challenge, says John Rogers, professor of materials science and engineering at the University of Illinois at Urbana-Champaign. The electrode-array design his group found to be most compatible with brain tissue is a mesh--solid sheets won't wrap around brain tissue as effectively. And adding silicon transistors to the mesh is more difficult than doing so on a solid substrate. Still, says Rogers, all the major pieces are in place and just need to be integrated. With further development and testing to prove the devices are safe, says Rogers, "we hope this will be the foundation for new higher quality brain-machine interfaces."
Gentler, softer electrodes wrap around the folds of the brain to take higher-resolution measurements.
>
Now a group of researchers is building biocompatible electronics on thin, flexible substrates. The group hopes to create neural interfaces that take higher-resolution measurements than what's available today without irritating or scarring brain tissue.
>
"A device like this would completely open up new avenues in all of neuroscience and clinical applications," says Gerwin Schalk, a researcher at the Wadsworth Center in Albany, NY, who is not affiliated with the silk electrode group. "What I foresee is placing a silk-based device all around the brain and getting a continuous image of brain function for weeks, months, or years, at high spatial and temporal resolution."
>
The silk electronics researchers say this is their next step, and one of the major promises of the technology. They've already demonstrated thin, flexible silicon transistor arrays built on silk, and tested them in animals--just not in the brain yet. Schwartz says other groups have recognized the importance of multiplexing and signal amplification, but have been working with rigid circuit boards that are not as biocompatible. Adding these active components would reduce the number of wires needed in these implants, which today require one wire per sensor. And active devices could respond to brain activity to provide electrical stimuli, or release drugs. (One of the collaborators on the silk project, David Kaplan at Tufts University, has demonstrated that silk devices implanted in the brain in small animals can deliver anti-epilepsy drugs.)
Adding transistors to the electronics is currently a design challenge, says John Rogers, professor of materials science and engineering at the University of Illinois at Urbana-Champaign. The electrode-array design his group found to be most compatible with brain tissue is a mesh--solid sheets won't wrap around brain tissue as effectively. And adding silicon transistors to the mesh is more difficult than doing so on a solid substrate. Still, says Rogers, all the major pieces are in place and just need to be integrated. With further development and testing to prove the devices are safe, says Rogers, "we hope this will be the foundation for new higher quality brain-machine interfaces."
Comment