Non-invasive transcranial alternating current stimulation (tACS)

Transcranial alternating current stimulation (tACS), similarly to tDCS, involves passing of weak electrical currents through the brain via electrodes placed on the scalp. In contrast to tDCS, however, the tACS induces a bi-directional current flow at variable frequencies.

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This way the frequency of stimulation can be selected to match the naturally occurring brain oscillations and to amplify specific cortical rhythms.