Transcranial electric stimulation (TES)

Non-invasive brain stimulation (NIBS) techniques

Transcranial electric stimulation (TES) with low­ intensity (0,5 мА – 2 мА) direct current (tDCS) or alternating current (tACS, tRNS) is used to generate neuromodulations in spontaneous neuronal activity. Physiological studies have demonstrated that DC flows through the skull and the outer layers of the cortex, modifies neuronal crossmembrane resting potentials, influences the level of neuronal excitability, and modulates firing rates. Depending on the orientation of the cells with respect to the current, the membrane potentials can be hyperpolarized (anodal stimulation) or depolarized (cathodal stimulation) by several mV. This change in neuronal excitability effects several alterations in brain function, including motor, sensory, and high-level cognitive function. On the other hand, tACS demonstrate frequency-dependent and entrainment effects, presumably, interacting with endogenous oscillatory activity. This method is actively used in medicine and research.