Analysis And Optimization Of Spatial And Temporal Characteristics Of Induced Electric Field In Whole Brain Under Rhythmic Weak Magnetic Stimulation

Rhythmic weak magnetic stimulation is a non-invasive brain modulation technique that has a significant effect in the treatment of neuropsychiatric diseases such as Alzheimer,epilepsy and Parkinson.Compared with transcranial magnetic stimulation,rhythmic weak magnetic stimulation has the characteristics of adjustable rhythm,low magnetic field amplitude,deep stimulation depth and brain domain coordination.However,the distribution of induced electric field in the brain and the stimulation mechanism on neurons are not clear.In this dissertation,the calculation model of rhythmic weak magnetic stimulation is constructed to get the distribution of the induced electric field.And on this basis,the stimulation model is optimized from the perspective of time and space to achieve a best stimulation effect.The main work of this dissertation is as follows:Firstly,the real brain model is constructed by using the three-dimensional reconstruction software mimics based on the MRI brain image.The calculation model of rhythmic weak magnetic stimulation is established to calculate the distribution of induced electric field and analyze its temporal and spatial characteristics.Secondly,the rhythmic weak magnetic stimulation model is optimized from the perspective of space and the electric field distributions of optimized models are analyzed,which describes the variation of electric field distribution with space.The spatial optimization model based on the improved spatial structure of the coil deepens the stimulation depth and weakens the electric field strength of the surface structure.Finally,the rhythmic weak magnetic stimulation model is optimized from the perspective of time and the electric field distributions of optimized models are analyzed,which describes the variation of electric field distribution with time.The time optimization model based on the time interference strategy achieves the localized stimulation effect for the target region.In addition,the pyramidal neuron model of hippocampal CA1 region is established,and the law of weak electric field regulation on neuronal discharge activity is analyzed.It's proved that weak electric field can regulate neuronal discharge activity by regulating the discharge time of neurons.In this dissertation,the temporal and spatial characteristics of electric field distribution of d TMS in brain are studied,and models are optimized from the perspective of time and space.The mechanism of d TMS regulation of brain neurons is further understood,which is of great contribution for clinical study of rhythmic weak magnetic stimulation.