Effects of Transcranial Direct Current Stimulation (tDCS) on Cognition in Patients with Drug-Resistant Focal Epilepsy: A Critical Review.

The relentless pace of scientific and technological advancement has heralded substantial innovations within the field of medicine. Among these advancements, Transcranial Electrical Stimulation emerges as a notable technology, and its potential application in the context of refractory epilepsy holds promise. The purpose of this paper is to investigate the effects of Transcranial Direct Current Stimulation (tDCS) on cognitive deficits in patients with focal refractory epilepsy. In the present article, we provide a critical review. PICOS framework was applied, while PRISMA and ROBINS-I guidelines were implicated in order to establish methodological rigor and validity. Results showed that cathodal (-) tDCS in patients with focal refractory epilepsy, in the epileptogenic area, with a current intensity of 1-2 mA, lasting 20-40 min once a day, for a total period of 5-14 days, may result in a reduction in the frequency of seizures and the epileptiform discharge rate. In addition, patients show cognitive improvement in the areas of working memory and attention. In conclusion, while there are available data on tDCS for a range of diseases, data in patients with focal refractory epilepsy are relatively limited and methodologically heterogeneous, despite positive evidence for its functional value. Further study is needed to fully elucidate the mechanisms of action and potential benefits.