Transcranial Focused Ultrasound Modulates Electrical Behavior of the Neurons: Design and Implementation of a Model

Abstract

Background: Recently, ultrasonic neuromodulation research has been an important and interesting issue. Ultrasonic neuromodulation is possible by the use of low-intensity transcranial focused ultrasound (tFUS) to stimulate or inhibit the neural structures. The primary capability of this method is the improvement in the treatment progress of certain neurological and psychiatric disorders noninvasively. tFUS is able to modulate ionic currents and neural depolarization, causing the alteration in electrical properties of neurons. Objective: The study aims to investigate the effect of tFUS waves on the electrical behavior of neurons using the simulation method. Material and Methods: In the first part of this simulation study, the propagation of tFUS waves throughout the head was simulated to calculate the value of acoustic pressure at the cortex. In the second part, cortical neurons were simulated by a simple model of spiking neurons proposed by Izhikevich for three common dynamics. Then, the capacitance model was proposed to determine the alteration in the electrical behavior of the neurons during tFUS stimulation. Results: At the resting state, the electric potential of the neuron’s membrane through the tFUS stimulation has an amplitude of about 30 mv with the similar oscillatory behavior of the acoustic waveform; while,the ultimate electrical behavior of the neuron’s membrane indicates a decrease in the electric potential when the neurons fire. Conclusion: The electrical behavior of the neuron and the range of its membrane voltage modulated during ultrasonic stimulation. The reduction in the amplitude of membrane potential was observed while neuron spikes.

Ultrasonic Retinal Neuromodulation and Acoustic Retinal Prosthesis

“…If such an acousto-thermal effect exists, according to the finding by Farah et al [ 46 ], membrane current may be determined by the change rate of the temperature. Interestingly, a recent study suggested that altered membrane capacitance could underlie the ultrasonic neural activation [ 56 ], echoing with one of the two primary hypotheses of opto-thermal stimulation.…”

tFUSFormer: Physics-Guided Super-Resolution Transformer for Simulation of Transcranial Focused Ultrasound Propagation in Brain Stimulation

“…Therefore, sophisticated models are required to account for significant attenuation and heating effects, especially as the waves traverse the skull [24]. On the other hand, simulations of low-intensity, low-frequency tFUS focus on neuromodulation, aiming to alter neural activity without permanent tissue alteration [25]. These models have minimal adverse effects and generally require less sophisti-cated modeling due to fewer physical variations, especially attenuation during propagation.…”