Parallel inhibition of cortico-muscular synchronization and cortico-spinal excitability by theta burst TMS in humans

Murat Saǧlam, Kaoru Matsunaga, Nobuki Murayama*, Yuki Hayashida, Ying Zu Huang, Ryoji Nakanishi

*Corresponding author for this work

Research output: Contribution to journalJournal Article peer-review

16 Scopus citations


Objective: To investigate the after-effects of theta burst TMS (TBS) on cortico-muscular synchronization, and on cortico-spinal excitability, in humans. Methods: We studied 10 healthy subjects using a continuous paradigm of TBS (cTBS), i.e. 600 pulses in 40 s. Before and after the cTBS, coherence function was computed as a measure of cortico-muscular synchronization by recording electroencephalogram (EEG) from 19 scalp sites and electromyogram (EMG) from right first dorsal interosseous (FDI) muscle during the isometric contraction. In a separate experiment, motor-evoked potentials (MEPs) in response to single TMS pulses were recorded from the FDI muscle before and after the cTBS, to measure cortico-spinal excitability. Results: When the cTBS was applied over the left primary motor cortex (M1), the beta-band cortico-muscular coherence for the C3 scalp site, as well as the MEP amplitude significantly decreased in 30-60 min, and then recovered to the original levels in 90-120 min. Neither sham stimulation nor cTBS applied over 2 cm posterior to M1 produced significant effects. Conclusions: cTBS-over-M1 can inhibit the cortico-muscular synchronization in parallel with the decline of cortico-spinal excitability. Significance: Our results provide the first evidence that TBS can efficiently alter the functional cortico-muscular coupling in humans.

Original languageEnglish
Pages (from-to)2829-2838
Number of pages10
JournalClinical Neurophysiology
Issue number12
StatePublished - 12 2008


  • Cortico-muscular coherence
  • Isometric contraction
  • Motor-evoked potentials
  • Repetitive transcranial magnetic stimulation
  • Theta burst stimulation


Dive into the research topics of 'Parallel inhibition of cortico-muscular synchronization and cortico-spinal excitability by theta burst TMS in humans'. Together they form a unique fingerprint.

Cite this