Enhancement of Neuromodulation with Novel Pulse Shapes Generated by Controllable Pulse Parameter Transcranial Magnetic Stimulation.

摘要: Abstract Background Standard repetitive transcranial magnetic stimulation (rTMS) devices generate bidirectional biphasic sinusoidal pulses that are energy efficient, but may be less effective than monophasic induce a more unidirectional electric field. To enable pulse shape optimization, we developed controllable parameter TMS (cTMS) device. Objective We quantified changes in cortical excitability produced by conventional and three rectangular-shaped cTMS pulses, one two (in opposite directions), compared their efficacy modulating motor evoked potentials (MEPs) of cortex. Methods Thirteen healthy subjects completed four sessions 1 Hz rTMS the left In each session, field had shapes. Excitability due to were measured applying probe before after rTMS, comparing resultant MEP amplitudes. Separately, latency MEPs pulses. Results While generated significant mean inhibitory effects subject group, cosine did not. The strongest inhibition resulted from rectangular with dominant induced current posterior–anterior direction. depended significantly on shape. Conclusions is an important factor rTMS-induced neuromodulation. standard showed smallest effect excitability, while greatest was observed for asymmetric, unidirectional, pulse. Differences across various shapes suggest activation distinct subsets microcircuitry.