Graduate Defense: FNU Tala

Dissertation Information

Title: On-Chip Active Pulse-Clamp Stimulation (Apcs) For Rapid Recovery, Charge-Balanced Neural Stimulation

Program: Doctor of Philosophy in Electrical and Computer Engineering

Advisor: Dr. Ben Johnson, Electrical and Computer Engineering

Committee Members: Dr. Nader Rafla, Electrical and Computer Engineering and Dr. Kurtis Cantley, Electrical and Computer Engineering

Abstract

Neurostimulations are widely utilized to modulate brain and nervous system functions for therapeutic purposes. Traditional neurostimulation involves applying a direct current delivered to the excitable tissues to elicit neural responses. There is a growing demand for a robust, rapid stimulation system that ensures chronic safety through charge balancing in vivo. This work is a compilation of integrated and board-level stimulators, an innovative stimulation technique, and a distributed modeling method. Chapter one introduces MEDUSA, a cost-effective, multi-functional neurostimulation system that achieves multi-channel, arbitrary stimulation for neuroscience research. Chapter two delves into a scripted distributed model framework facilitating the co-design of neural recording frontends and stimulators, crucial for close-loop applications necessitating electrode interface characterization. Chapter three focuses on a small, low-cost, wireless neurostimulator designed for rodent deep brain stimulation applications. Chapter four serves as an introduction to Active Pulse-Clamp Stimulation (APCS), presenting the linear APCS theory and a validated system proficient in rapid electrode interface recovery while maintaining charge balancing. Chapter Five introduces an on-chip APCS system, integrating both linear APCS and slewing APCS modes. This innovative system employs the slewing mode for swift charge recovery and ensures charge balancing through the linear mode.