Multiscale Investigation of Low Intensity Transcranial Focused Ultrasound Neuromodulation in in-vivo Rodent Models

Abstract

Transcranial focused ultrasound (tFUS) is a noninvasive neuromodulation method that modulates neural activity using mechanical pressure waves. tFUS has emerged as a promising noninvasive neuromodulation method with millimeter scale resolution and propensity to stimulate deep structures. Researchers have reported tFUS induced short term excitation or inhibition at cortical or deep brain. Currently, there are no reports of long term effects elicited by tFUS. The ability to use tFUS to non-invasively induce long term changes in the brain expands the clinical utility of tFUS. In order to explore the long term effects of tFUS on synaptic connectivity, we first evaluated our setup by examining the ability of tFUS to reliably induce short term changes to in vivo rats. After establishing our setup, we applied pulsed ultrasound to encode temporal information into the hippocampus to induce long term depression in 5 adult rats. Further investigations are needed to explore the underlying mechanisms.