Development of a Novel Tool to Study Mechanisms of Recording Instability in Implanted Silicon Microelectrode Arrays
Daniel R. Merrill, Ph.D.

Wednesday, March 26, 2008 7 PM
CLU - Richter Hall, Ahmanson Science Building

The mechanisms underlying performance degradation of chronically implanted silicon microelectrode arrays in the central nervous system remain unclear. One proposed mechanism is increased electrical impedance due to the foreign body reaction at the electrode-brain tissue interface. In this seminar I will present in vivo experiments directed towards understanding the failure mechanisms of chronically implanted devices. Within the scope of these experiments, a novel tool was developed for characterizing temporal changes at the electrode-brain tissue interface. This tool allows one to evaluate in vivo impedance, cytokine release, the ability to perform electrophysiological recordings, and histological changes at the electrode-brain tissue interface within a single experimental animal, and eliminates certain confounding issues with previous attempts at in vivo impedance measurement.

Daniel R. Merrill, Ph.D.
Alfred E. Mann Foundation for Scientific Research

Dan Merrill earned his B.S. and M.Eng. in Electrical Engineering at Cornell University.  He then spent 11 years in industry, working for Quinton Instrument Company developing biomedical instrumentation. From 1995 through 2002 Dan earned his Ph.D. at Case Western Reserve University at the Applied Neural Control Laboratory, studying the mechanisms of charge injection at the electrode-tissue interface.  He then spent three years on a Fellowship at the University of Utah studying the mechanisms underlying failure of chronically implanted devices.  Dan now works for the Alfred E. Mann Foundation for Scientific Research, developing novel medical technology.