Depression of motor cortex excitability by low‐frequency transcranial magnetic stimulation

@article{Chen1997DepressionOM,
  title={Depression of motor cortex excitability by low‐frequency transcranial magnetic stimulation},
  author={R. Chen and Joseph Classen and Christian Gerloff and Pablo A. Celnik and Eric M. Wassermann and Mark Hallett and Leonardo G. Cohen},
  journal={Neurology},
  year={1997},
  volume={48},
  pages={1398 - 1403}
}
We studied the effects of low-frequency transcranial magnetic stimulation (TMS) on motor cortex excitability in humans. TMS at 0.1 Hz for 1 hour did not change cortical excitability. Stimulation at 0.9 Hz for 15 minutes (810 pulses), similar to the parameters used to induce long-term depression (LTD) in cortical slice preparations and in vivo animal studies, led to a mean decrease in motor evoked potential (MEP) amplitude of 19.5%. The decrease in cortical excitability lasted for at least 15… 

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