Effects of Transcranial Direct Current Stimulation on Expression of Immediate Early Genes (IEG's)

: Transcranial direct current stimulation (tDCS) has been utilized in human studies to modulate a multitude of psychological, cognitive, and psychiatric disorders. There have been positive behavioral results in human subjects, but our knowledge of biological processes occurring during stimulation to elicit behavioral outcomes is limited. Our study utilizes a rodent tDCS (R-tDCS) model in which Sprague Dawley rats receive tDCS in order to examine whether tDCS affects neuronal activation. We examined two immediate early genes (IEG's), cFos and zif268, in order to discern if tDCS affects neuronal activation. Our findings indicate that tDCS does affect neuronal activation by means of IEG induction and that there is dose dependence between current intensity used and mRNA levels of IEG's. These findings are important because they show biologically tDCS affecting neuronal activation. This study aided the scientific community in better understanding what is occurring biologically during tDCS.