Collective Dynamics And Signal Synchronous Transmission Of Neural Networks Under Electromagnetic Field Regulation

Researches on brain science have been carried out in many fields.At present,the more mature research is neural dynamics.It uses mathematical models,theoretical analysis and computer simulation to study the real biophysical models in neurons and nervous systems in biology.Neuronal electrical activity and information processing play an important role in the neural system.Different neuronal discharge patterns represent different coding meanings and biological functions.In the coupled neural network,the vibration resonance,trigger synchronization and weak signal propagation caused by high-frequency stimulation of the neural system are closely related to the physiological function of the brain.Because the electromagnetic field can regulate the neural activity in the brain,several mathematical models of neurons are used to study the dynamics of nervous system in electromagnetic driven single neuron,chain neural network and multilayer feedforward neural network.The main contents of this paper are as follows:1.Based on the improved electromagnetic driven neuron model,the effects of electromagnetic radiation on the discharge mode of a single neuron and the collective dynamics in a chain network are studied.First,the high-low frequency electromagnetic radiation stimulation and white Gaussian noise are taken into account on a single neuron,and the transformation of the electrical activity mode of the neuron is studied by changing the bifurcation parameters.The electrical activity mode of neurons is transformed.Moreover,double vibration resonance can be observed under high-low frequency current stimulation and weak electromagnetic driven,while only single vibration resonance occurs under strong electromagnetic driven,compared with electromagnetic driven.Considering electromagnetic field effects weaken neuronal vibration resonance and inhibit multiple vibration resonance.In addition,the collective dynamics driven by electromagnetic is studied in the chain neural network.It is found that when the coupling intensity of electromagnetic field is relatively large,all neurons in the chain neuron network are excited,and the spikes of neurons remain synchronous.The firing rate becomes larger.When the chemical autapse is negative feedback,the wave can not propagate from the central neuron to the end of the chain neural network,while the autapse is positive feedback,the opposite is true.2.A multi-layer feedforward neural network is constructed to simulate and study the factors that affect the trigger synchronism and weak signal propagation ability of neurons.In excitatory and excitatory inhibitory neural networks,by discussing the effects of noise and interlayer synaptic weight on the propagation ability of subthreshold excitatory postsynaptic current,it is found that weak signals in neural networks propagate stably with the best noise intensity.Different noise intensities enhance or weaken the system's response to weak signals.And under larger interlayer synaptic weights,weak signals can be stably transmitted to the output layer,but for smaller synaptic weights,weak signal propagation may not reach the output layer.Moreover,the neurons in the output layer fully synchronously trigger under appropriate synaptic weights and noise.3.The effects of electromagnetic induction,noise and synaptic weight on the propagation ability of synchronous and aperiodic subthreshold electrical signals are studied in multilayer neural networks.It is found that the optimal noise intensity can maintain the optimal state of signal propagation,but the optimal propagation is weakened by increasing the electromagnetic driven.And compared with the case without considering electromagnetic radiation,increasing electromagnetic radiation will reduce the propagation ability of weak signal.As the intensity of electromagnetic radiation increases,the time required for weak signals to reach the output layer becomes longer.moreover,a constant input weak signal combined with a suitable noise intensity will stably propagate the weak signal to the rear layer under the appropriate electromagnetic field.When the system is in a strong magnetic field,weak signal transmission fails due to the small synaptic weight.