Dissertations and Theses

Date of Award

2024

Document Type

Dissertation

Department

Biomedical Engineering

First Advisor

Lucas C. Parra

Keywords

Neural Engineering, Neuroscience, Neuromodulation, Brain Stimulation, tDCS, Biomedical Engineering

Abstract

Research thus far on noninvasive, transcranial electric stimulation have produced mixed results from in vivo human experiments. This work tests the hypothesis that applying higher stimulation intensities would induce intracranial electric fields that more closely match the higher magnitudes used in animal and in vitro studies and subsequently yield more robust effects. As done commonly in the literature, we targeted the motor cortex (M1), specifically in the context of neuroplastic changes taking place during motor learning in healthy adult humans. This work also seeks a better understanding of the neural correlates underlying motor skill learning.

Through multiple large-sample studies, this work demonstrates the feasibility of high-intensity tDCS up to 6 mA. Contrary to our hypothesis, even targeted, high-intensity tDCS may not produce consistent modulation effects on motor learning. While the latest outcomes may cast further doubt over the efficacy of tDCS, they are nonetheless specific to this configuration. They provide support for the notion that the neural substrate underlying motor learning is highly complex, suggesting that further refinements may be necessary to optimize stimulation techniques for in vivo applications in humans.

Share

COinS
 
 

To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.