Robinson , Jacob2019-05-172019-05-172018-052018-04-20May 2018Wickens, Amanda. "Magnetoelectric Materials for Miniature, Wireless Neural Interfaces." (2018) Master’s Thesis, Rice University. <a href="https://hdl.handle.net/1911/105756">https://hdl.handle.net/1911/105756</a>.https://hdl.handle.net/1911/105756Developments in wireless neuromodulation technologies have lead to new treatments for neurological disorders and new methods of probing neural circuits in humans and animal models. Miniaturized and wirelessly powered biomedical implants are being developed in order to minimize the perturbation and damage to the neural circuits and surrounding tissue. However, developing devices capable of transmitting sufficient power in small form factors remains a challenge. Conventional wireless neural stimulation devices need to be connected to a bulky battery pack or coil of wire that, when miniaturized, suffers from reduced power transfer, high angle dependence, and requires high ~MHz frequency electromagnetic fields to carry the power. This limits the applications for any given device and can cause a negative host response due to the larger implants and leads. Here we show magnetoelectric devices capable of transforming external magnetic fields to controllable electric fields strong enough to wirelessly stimulate targeted neural regions in freely moving rats with no genetic modification. We found that by coupling a piezoelectric and magnetostrictive material at an acoustic resonance, magnetoelectric films can stimulate cells in vitro when we apply an external magnetic field. We are currently working to further show that these electric fields are strong enough to stimulate activity wirelessly by powering implanted electrodes in freely moving rats. Furthermore, in contrast to traditional inductive coupling, we show magnetoelectric materials are scalable and still capable of generating large voltages with a small device footprint. Our results demonstrate that magnetoelectric materials can be used to develop versatile lightweight wireless neural implants. We lay the foundation for further developing these materials to be used for many different applications in neuroscience.application/pdfengCopyright is held by the author, unless otherwise indicated. Permission to reuse, publish, or reproduce the work beyond the bounds of fair use or other exemptions to copyright law must be obtained from the copyright holder.NeuromodulationMagnetoelectricThesis2019-05-17