Miniaturizing wireless biomedical devices, both for recording and stimulation purposes, has long been a challenge for the engineering community. A dramatic decrease in the size of such devices promises less invasive treatment for a myriad of illnesses, but has proven to be difficult to implement while maintaining wireless power. Conventional techniques of wireless power transfer lose their abilities to do so as their size is decreased, leaving a question of implementation for the biomedical engineering community.
We have successfully created magnetoelectric devices capable of transforming external magnetic fields to controllable electric fields strong enough to wirelessly stimulate targeted neural regions in freely moving rats without genetic modification. By coupling a piezoelectric and magnetostrictive material at an acoustic resonance, the application of an external magnetic field allows for the stimulation of cells, both in vivo and in vitro. Having been able to successfully power implanted electrodes in freely moving rats, we demonstrate the ability to wirelessly modulate neural, and thus behavioral, activity. In contrast to traditional inductive coupling, magnetoelectric materials are scalable and remain capable of generating large voltages with a small device footprint. Our results provide the groundwork to create much smaller implantable devices for neural modulation in the near future.
My involvement in this project, led by Amanda Wickens of the Robinson Lab, has been the design and manufacture of an implant for both in vivo and in vitro testing, as well as the analysis of rodent behavior using a version of DeepLabCut, which can be found on my GitHub here.