Systems, apparatus and methods are described for applying electric current to neurons in the brain to treat disorders and to improve motor and/or memory functions in a patient. In a method according to the invention, an electrode is positioned adjacent to and spaced from the skin surface of the patient's head and an electric current is applied through the electrode to a target region in the brain to modulate one or more neurons in the target region. The electrode is housed within an enclosure and spaced from the skin surface so that the electrode does not directly contact the patient's tissue, which reduces the potential for collateral tissue damage or necrosis and shields the electrode from the patient's tissue which substantially inhibits Faradic products (e.g., H+, OH−, H2O2) of the electrode from reaching the target site.