Lifting the veil on the dynamics of neuronal activities evoked by transcranial magnetic stimulation
- University of Tübingen, Germany
- Max Planck Institute for Biological Cybernetics, Germany
Abstract
Transcranial magnetic stimulation (TMS) is a widely used non-invasive tool to study and modulate human brain functions. However, TMS-evoked activity of individual neurons has remained largely inaccessible due to the large TMS-induced electromagnetic fields. Here we present a general method providing direct in vivo electrophysiological access to TMS-evoked neuronal activity 0.8-1 ms after TMS onset. We translated human single-pulse TMS to rodents and unveiled time-grained evoked activities of motor cortex layer V neurons that show high-frequency spiking within the first 6 ms depending on TMS-induced current orientation and a multiphasic spike-rhythm alternating between excitation and inhibition in the 6-300 ms epoch, all of which can be linked to various human TMS responses recorded at the level of spinal cord and muscles. The advance here facilitates a new level of insight into the TMS-brain interaction that is vital for developing this non-invasive tool to purposefully explore and effectively treat the human brain.
Article and author information
Author details
Funding
Hertie Institute for Clinical Brain Research
- Cornelius Schwarz
- Martin A Giese
- Ulf Ziemann
Centre for Integrative Neuroscience, University of Tübingen
- Cornelius Schwarz
- Martin A Giese
- Ulf Ziemann
Max Planck Institute
- Bingshuo Li
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All experimental procedures involving animals were approved by the Tübingen Regional Council (license number: N1/16) and performed in accordance with the German Animal Welfare Act.
Copyright
© 2017, Li et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Lifting the veil on the dynamics of neuronal activities evoked by transcranial magnetic stimulation
eLife 6:e30552.
https://doi.org/10.7554/eLife.30552
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