Measurements and models of electric fields in the in vivo human brain during transcranial electric stimulation

Transcranial electric stimulation aims to stimulate the brain by applying weak electrical currents at the scalp. However, the magnitude and spatial distribution of electric fields in the human brain are unknown. We measured electric potentials intracranially in ten epilepsy patients and estimated electric fields across the entire brain by leveraging calibrated current-flow models. When stimulating at 2 mA, cortical electric fields reach 0.8 V/m, the lower limit of effectiveness in animal studies. When individual whole-head anatomy is considered, the predicted electric field magnitudes correlate with the recorded values in cortical (r = 0.86) and depth (r = 0.88) electrodes. Accurate models require adjustment…

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  National Institutes of Health

  Awards: R01MH107396, R01MH092926, R44NS092144, R41NS076123
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  National Institute of Mental Health
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  National Institute of Neurological Disorders and Stroke