Electrodes are placed on the earlobes, maxilla-occipital junction, mastoid processes or temples. Despite the long history of<unk> , its underlying principles and mechanisms are still not clear.<unk>  stimulation of 1 mA (milliampere) has shown to reach the thalamic area at a radius of 13.30 mm.<unk>  has shown to induce changes in the electroencephalogram, increasing alpha relative power and decreasing relative power in delta and beta frequencies.<unk>  has also shown to reach cortical and subcortical areas of the brain, in electromagnetic tomography and functional MRI studies.<unk>  treatments have been found to induce changes in neurohormones and neurotransmitters that have been implicated in psychiatric disorders: substantial increases in beta endorphins, adrenocorticotrophic hormone, and serotonin; moderate increases in melatonin and norepinephrine, modest or unquantified increases in cholinesterase, gamma-aminobutyric acid, and dehydroepiandrosterone, and moderate reductions in cortisol.
Cranial electrotherapy stimulation
Electrical brain stimulation
Magnetic seizure therapy
Electric acoustic stimulation
Non-invasive cerebellar stimulation
Auditory brainstem implant
Transcranial random noise stimulation
Deep brain stimulation