The Study Of Relationship Between Local Field Potential And Neuronal Firing Under Epileptic Interictal Discharge

Epilepsy is a chronic disease with high morbidity.Because of the varable effect of treatment,understanding the epileptic seizure mechanism is crucial.EEG signals are an important indicator in epilepsy studies.EEG signals of epilepsy can be divided into ictal and interictal periods.Since ictal and interictal discharges have similar pathways,it's?meaningful to study the interictal discharge.Past research suggested that epilepsy was caused by the simultaneous exciting discharge of neurons,and recent clinic studies had suggested that there were multiple firing patterns of neurons in interictal discharge.Therefore,this article attempted to explore whether neurons fired simultaneously or there are multiple modes of distribution under interictal discharge.In this paper,the rat penicillin partial epilepsy model was used as the experimental object.With the aid of microelectrode array,the local field potentials and the spikes of neurons under the interictal discharge near the injection point were extracted.The time domain and frequency domain were respectively used to describe the relationship between the two signals,to explore the neuron's firing patterns under interictal discharges.Specific content includes:(1)The rat epilepsy model of penicillin was established successfully.The behavioral characteristics of this model were consistent with the behavioral characteristics of human clinical epilepsy.The temporal and frequency domain characteristics of rat on field potential signals were also consistent with other local penicillin epilepsy models.(2)We studied the time-domain relationship between the rat field potential and neuron firing under interictal discharges,and analyzed the firing pattern of neurons at different periods of interictal discharge,and further analyzed the firing pattern of neurons during the spike and slow wave periods.We found that there were multiple firing patterns of neurons in interictal discharge.(3)The frequency domain relationship between the rat field potential and neuron firing under the interictal discharges was studied.First,the local field potential in the 1-20 Hz band was found to be related to the interictal discharge,and then the above frequency band of the field potential was extracted.Based on the phase of the signal,the phase relationship between neuron firing and field potential under interictal discharge was analyzed.It was found that there were two kinds of phase-locked relationship between neurons and interictal discharge.In summary,in rat epilepsy model of penicillin,interictal discharges are not purely caused by synchronized neuron firing,but there are multiple neurons' firing patterns of distribution,which indicates that epilepsy may be caused by a complex network structure,and therefore needs to be further studied from the electrophysiological point of view.