Active MEMS Neural Clamps

Arizona State University-Tempe Campus, Tempe AZ

Investigators

Abstract

DESCRIPTION (provided by applicant): ACTIVE MEMS NEURAL CLAMPS In the past decade, significant technological and scientific advances have led to the development of neuroprosthetic devices for motor control. An important aspect in the further advancement of the control systems for such devices will be the ability to obtain stable spatiotemporally distributed recording of neural activity chronically. Similarly, neural interfaces that can provide spatiotemporally distributed stimulation of neural tissue are required. In this project, we are focusing on the development of a novel approach of recording distributed neural activity from the peripheral nervous system, in particular the mammalian spinal roots. The goal is to model, design, fabricate, test and characterize Microelectromechanical System (MEMS) based neural electrodes that actively clamp onto the spinal roots. This clamping mechanism will provide a reversible secure attachment mechanism to ensure reliable recording of the neural signals. The clamping will be driven by the body temperature at site of the implant. The clamping can be temporarily reversed for repositioning during the implant procedure by local perfusion of cooled saline solutions. The fabrication, guided by a finite element modeling approach, will use silicon wafer batch processing techniques that are compatible with integrated circuit manufacturing in order to enable future development of on-chip electronics for filtering, amplification and signal processing. The silicon wafer fabrication also enables future development of low-cost devices. With batch processing, we can vary the electrode and device characteristics on a single wafer to optimize performance. Several electrode configurations on the same device will be evaluated initially using amphibian nerve, then with fixed rodent nerve, and ultimately in real-time by recording autonomous respiratory activity from rat cervical spinal roots and the phrenic nerve. Ability to place the electrodes on multiple lumbosacral spinal roots will be evaluated. These results will guide the redesign of the electrodes. The novel design allows capability for repositioning of multiple spatially distributed implantable electrodes. Such electrodes will advance our capabilities of scientific investigation of neural function in awake subjects and in the development of advanced neuroprosthetic products for rehabilitation.