Researchers from Carnegie Mellon University have recently received a $1.95 million grant from the National Institutes of Health (NIH) to 3D print a new type of neural probe to record neurological information. This technique will greatly increase accessibility to brain tissue, allow for more electrodes to fit into a region of the brain, and will enable researchers to evaluate new electrode patterns within hours. This NIH grant was presented to Carnegie Mellon’s Rahul Panat, an associate professor of mechanical engineering, and Eric Yttri, an assistant professor of biological sciences, and is a part of the federal Brain Research through Advancing Innovative Neurotechnologies (BRAIN) Initiative.
“This research proposes to use a novel additive manufacturing (AM) method that uses 3D nanoparticle printing to fabricate customizable, ultra-high density neural probes, such as brain-machine interfaces or BMIs,” said Panat, a member of Carnegie Mellon’s Next Manufacturing Center. “The recording densities of the probes will be an order of magnitude higher than that made by any current method.”
Shortcomings of Current Electrodes
Traditional silicon electrode arrays are both fragile and expensive, making them inapplicable in many circumstances. These arrays typically have very low electrode density as well, making them unable to yield resolutions needed for interventions such as brain implants. By using 3D printing to create neural probes, however, Panat and Yttri could potentially overcome these shortcomings regarding structure, cost, and reliability. Leveraging their unique backgrounds, the two are aiming to create a 3D printed microelectrode array for the first time ever.
“With fMRI we can see the whole brain, but the temporal and spatial resolution are not where we need them to be,” explained Yttri. “Electrodes can give us millisecond, single neuron resolution, but even with the most recent advances you might only be able to get information from 300 or 400 neurons at a time. With my expertise in neuroscience and Rahul’s pioneering 3D printing technique based on aerosol jet technology, we decided to combine our interests to bridge this gap that exists between the two ways neuroscience is classically done.”
A 3D Printed Solution
The researchers explain that this novel electrode system could provide unprecedented flexibility in the electrode array’s function.
“If you want an electrode, typically you go to a supplier who offers 10 options, and you have to make one of those options work for any experiment,” explains Yttri. He added that by 3D printing the electrodes, they can place them as close or far from each other as necessary. This technique also minimizes unnecessary damage by simplifying the implantation of these electrodes, according to Yttri.
Yttri and Panat’s goal is to eventually create brain-machine interfaces (BMIs) and other precise neurological devices. 3D printing these neural probes allows them to be customized specifically to each patient as well. Using structural MRI data, the electrode array would be tailored to model the individual’s brain curvature.
“We are applying the newest advances in microelectronics manufacturing to neuroscience in order to realize the next generation of tools for the exploration of the brain,” said Panat. “This research will lead to a more precise 3D mapping of neural circuits and precision neuroprosthetic devices that can restore significantly more of patients’ previously lost functionality. The research will also lead to new avenues for the treatment of neurodegenerative diseases such as paraplegia and epilepsy.”
— 3D Printing News (@3DPrintMaven) August 30, 2019