Neural Probe Utilizing Programmable Micro-coil Magnetic Stimulation

Micro-coil based magnetic stimulation has been shown to be an effective form of neural modulation [1]. Micro-coil devices have advantages over the more commonly used micro-electrodes due to the induced electric fields being spatially asymmetric, allowing for neuron orientation-based selectivity. Furthermore, the micro-coils do not require direct contact with biological tissue, allowing for complete encapsulation of the devices to maintain their stimulation efficiency over time and avoid electrochemical effects such as corrosion, hydrolysis, and other sources of damage to the tissue and probe. However, previous micro-coil based neural probes lack reconfigurable hardware causing their stimulation sites to be fixed post-insertion. The proposed stimulator integrates micro-coils, CMOS control circuitry, and additional nanofabrication processing to fabricate a neural probe with spatially programmable micro-coil based neurostimulation. In-vitro testing with mouse olfactory bulb slices was performed using a commercial MEA to record changes in neural spike behavior during micro-coil based neurostimulation.