Ultrasound Neuromodulation in an Earthworm

Neuromodulation is a way to directly target the nervous system through a stimulus that alters neuron activity. Neuromodulation uses invasive or non-invasive techniques to regulate neuron activity, and has been used for therapeutic purposes and management of neurological diseases. However, non-invasive techniques can not target specific areas. Focused ultrasound (FUS) neuromodulation is a promising non-invasive technique for clinical applications but the mechanisms are still not fully understood . We are developing a testbed to investigate the basic mechanisms of FUS neuromodulation. Our testbed uses an earthworm due to its simple nervous system and simple handling procedure. Preliminary results suggest that our testbed is capable of inducing action potentials in the earthworm’s ventral nerve cord using FUS. This paves the way for more in-depth experiments to investigate the optimum FUS parameters (pressure, pulse duration, repetition frequency, etc.), which can lead to a deeper understanding of the underlying mechanisms of FUS neuromodulation.