Propagation of Endogenous Electric Fields as a Possible Mechanism of Synchronization of Interictal Spikes in Rat Neocortex
The research concerning the impact of neural networks of brain by weak electric fields with parameters that are similar to the fields produced by electrical activity of the brain structures was conducted for several decades. Interest in such studies has increased recently due to the fact that methods of transcranial stimulation are now used for the treatment of various diseases. Using linear regression and correlation analysis methods we have established relationship between the potential value of interictal spike and the value of potential at the point of the cortex located a few millimeters from the generation point of the spike. Also, we observed a link between the occurrence of interictal spikes in one point of the cortex with simultaneous appearance of electric potentials in the neighboring areas. After the blockade of sodium channels in the recording point there was an increase of the coefficients of the linear regression and correlation coefficients, that showed that the effects of the electric fields of potentials are significant. In order to determine whether this was not the dependence of the random nature, the temporal sequence of one channel was shifted relative to another channel according to the law of random numbers. The value of the linear regression and correlation coefficients decreased by an order. Our results show that the electric potential of small interictal spike arising at one point of the cortex spreads to other areas with a short time delay.