Contents I. Introduction
Transcranial direct current stimulation (tDCS) is a non-invasive method that modifies the efficiency of neurotransmission in the stimulated cortical areas and triggers the processes of neuroplasticity influenced by a low direct current (up to 1–2 mA) [1]. At the beginning of the 21st century A. Priory and M.A. Nitsche proved that the use of low direct currents transcranially causes changes in the excitability and activity of the cerebral cortex during and after stimulation in animals and humans [2], [3]. A. Priory's research also showed in healthy participants that tDCS for long periods of time (about 10 minutes) causes persistent changes lasting about 1 hour in excitability after its elimination [3]. Depending on the type of current, stimulation can be positive (anodal), negative (cathodal) and placebo (sham). It has been proven that anodal tDCS of the primary motor cortex (M1) in healthy people increases the excitability of the cortex, while cathodal stimulation reduces [3]. Over the past 20 years of clinical practice, the method has used extensively in the field of psychiatry and neurology, especially in relation to such disorders as: migraine, depression, stroke, epilepsy [4], [5].
