Electroconvulsive therapy (ECT) is an effective treatment for specific psychiatric disorders. There are marked individual differences in seizure threshold in ECT, mainly attributable to variations in skull anatomy. The dose of the ECT electrical stimulus and anatomic positioning of transcranial electrodes determine the efficacy and cognitive side effects.1 However, control over intracerebral current density and its spatial distribution is inherently limited due to the high skull impedance and shunting of the electrical stimulus through the scalp.
Lisanby SH, Luber B, Sackeim HA, Finck AD, Schroeder C. Deliberate Seizure Induction With Repetitive Transcranial Magnetic Stimulation in Nonhuman Primates. Arch Gen Psychiatry. 2001;58(2):199-200. doi:10.1001/archpsyc.58.2.199