title: The effect of continuous theta burst stimulation over premotor cortex on circuits in primary motor cortex and spinal cord.
abstract: OBJECTIVE
  To understand the effect of continuous theta burst stimulation (cTBS) given to the premotor area, we studied the circuits within the primary motor cortex and spinal cord after cTBS over the dorsal premotor area (PMd).
  
  
  METHODS
  Three sets of parameters, including corticospinal excitability, short interval intracortical inhibition (SICI) and intracortical facilitation (ICF) and forearm reciprocal inhibition (RI) were tested.
  
  
  RESULTS
  Paralleling the effects of cTBS applied directly to the primary motor cortex, cTBS over the left PMd suppressed corticospinal excitability as measured by the change in the size of MEPs evoked by single pulse TMS over primary motor cortex. Premotor cTBS appeared to have a longer lasting, but no more powerful effect on corticospinal excitability than motor cTBS, however, unlike motor cTBS it had no effect on SICI or ICF. Finally, although premotor cTBS had no effect on spinal H-reflexes, it did reduce the third phase of RI between forearm extensor and flexor muscles.
  
  
  CONCLUSIONS
  Premotor cTBS is a quick and useful way of modulating excitability in cortical and possibly subcortical motor circuits.
  
  
  CONCLUSIONS
  Premotor cTBS can be used as an alternative to regular rTMS to evaluate cortical function, motor behaviours and the response to disease therapy.
authors.affiliation: Department of Neurology, Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Taipei, Taiwan.
authors.forename: Ying-Zu
authors.initials: YZ
authors.lastname: Huang
authors.forename: John C
authors.initials: JC
authors.lastname: Rothwell
authors.forename: Chin-Song
authors.initials: CS
authors.lastname: Lu
authors.forename: Jiunjie
authors.initials: J
authors.lastname: Wang
authors.forename: Yi-Hsin
authors.initials: YH
authors.lastname: Weng
authors.forename: Szu-Chia
authors.initials: SC
authors.lastname: Lai
authors.forename: Wen-Li
authors.initials: WL
authors.lastname: Chuang
authors.forename: June
authors.initials: J
authors.lastname: Hung
authors.forename: Rou-Shayn
authors.initials: RS
authors.lastname: Chen
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001703:Biophysics; D004558:Electric Stimulation / Q000379:methods; D004576:Electromyography / Q000379:methods; D019054:Evoked Potentials, Motor / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009044:Motor Cortex / Q000502:physiology*; D018482:Muscle, Skeletal / Q000294:innervation; D009415:Nerve Net / Q000502:physiology*; D009433:Neural Inhibition / Q000502:physiology; D009434:Neural Pathways / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology; D012018:Reflex / Q000502:physiology; D013116:Spinal Cord / Q000502:physiology*; D013826:Theta Rhythm; D013997:Time Factors; D050781:Transcranial Magnetic Stimulation / Q000379:methods; D055815:Young Adult