Effects of transcranial Direct Current Stimulation (tDCS) on cortical activity: Neuron-Astrocyte computational modeling study

Transcranial Direct Current Stimulation (tDCS) is a non-invasive brain stimulation technique that is affordable and easy to operate compared to other neuromodulation techniques. Despite this method is promising in treating neurological diseases and enhancing cognitive functions, the precise mechanism of the effect of this sub-threshold stimulation has not been understanded well. Understanding the mechanism is important in designing the proper protocol and system for the brain's electrical stimulation. The aim of this paper is to identify this mechanism with the neural modeling approach. As the results of some physiological studies have shown that under tDCS, sudden calcium signaling associated with calcium signaling of astrocyte cells in the brain are found, in the proposed model, this cell is considered as well as the main neurons and interneurons. The purpose of this model is to simulate the effect of tDCS on cortical activity related to the evoked response potential (ERP) and to compare with the actual results of previous experimental studies on rats. The results show that this model can simulate all the evidence of experimental studies. While the proposed purely neuronal model in previous studies could not simulate all the evidence