TY - JOUR
T1 - Differentiating transcranial magnetic stimulation cortical and auditory responses via single pulse and paired pulse protocols
T2 - A TMS-EEG study
AU - Poorganji, Mohsen
AU - Zomorrodi, Reza
AU - Hawco, Colin
AU - Hill, Aron T.
AU - Hadas, Itay
AU - Rajji, Tarek K.
AU - Chen, Robert
AU - Voineskos, Daphne
AU - Daskalakis, Anastasios A.
AU - Blumberger, Daniel M.
AU - Daskalakis, Zafiris J.
N1 - Funding Information:
The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: In the last 5 years, ZJD has received research and equipment in-kind support for an investigator-initiated study through Brainsway Inc and Magventure Inc. His work is supported by the Canadian Institutes of Health Research (CIHR), the Natural Sciences and Engineering Research Council (NSERC) of Canada, the National Institutes of Mental Health (NIMH), Brain Canada and the Temerty Family and Grant Family and through the Centre for Addiction and Mental Health (CAMH) Foundation and the Campbell Institute. DMB receives research support from CIHR, NIH, Brain Canada and the Temerty Family through the CAMH Foundation and the Campbell Family Research Institute. He received research support and in-kind equipment support for an investigator-initiated study from Brainsway Ltd. He is the site principal investigator for three sponsor-initiated studies for Brainsway Ltd. He also receives in-kind equipment support from Magventure for investigator-initiated research. He received medication supplies for an investigator-initiated trial from Indivior. TKR has received research support from Brain Canada, Brain and Behavior Research Foundation, BrightFocus Foundation, Canada Foundation for Innovation, Canada Research Chair, Canadian Institutes of Health Research, Centre for Aging and Brain Health Innovation, National Institutes of Health, Ontario Ministry of Health and Long-Term Care, Ontario Ministry of Research and Innovation, and the Weston Brain Institute. Dr. Rajji also received in-kind equipment support for an investigator-initiated study from Magstim, and in-kind research accounts from Scientific Brain Training Pro. DV has received research training fellowship funding from the Ontario Mental Health Foundation, an American Psychiatric Association/Eli Lilly research fellowship, and a CAMH postdoctoral fellowship and support from the Innovation Fund of the Alternative Funding Plan for the Academic Health Sciences Centres of Ontario. DV declares no biomedical interests or conflicts. MP, RZ, CH, ATH, IH, RC, and AAD have nothing to disclose.
Funding Information:
This study was supported by a Discovery Grant from the Natural Sciences and Engineering Research Council (NSERC) of Canada (JD) and a NARSAD Award from the Brain and Behavior Research Foundation (CH). Dr. Hawco was supported by a Banting Post-Doctoral Fellowship from the Canadian Institute of Health Research during part of this work.
Publisher Copyright:
© 2021
PY - 2021/8/1
Y1 - 2021/8/1
N2 - Objective: We measured the neurophysiological responses of both active and sham transcranial magnetic stimulation (TMS) for both single pulse (SP) and paired pulse (PP; long interval cortical inhibition (LICI)) paradigms using TMS-EEG (electroencephalography). Methods: Nineteen healthy subjects received active and sham (coil 90° tilted and touching the scalp) SP and PP TMS over the left dorsolateral prefrontal cortex (DLPFC). We measured excitability through SP TMS and inhibition (i.e., cortical inhibition (CI)) through PP TMS. Results: Cortical excitability indexed by area under the curve (AUC(25-275ms)) was significantly higher in the active compared to sham stimulation (F(1,18) = 43.737, p < 0.001, η2 = 0.708). Moreover, the amplitude of N100-P200 complex was significantly larger (F(1,18) = 9.118, p < 0.01, η2 = 0.336) with active stimulation (10.38 ± 9.576 µV) compared to sham (4.295 ± 2.323 µV). Significant interaction effects were also observed between active and sham stimulation for both the SP and PP (i.e., LICI) cortical responses. Finally, only active stimulation (CI = 0.64 ± 0.23, p < 0.001) resulted in significant cortical inhibition. Conclusion: The significant differences between active and sham stimulation in both excitatory and inhibitory neurophysiological responses showed that active stimulation elicits responses from the cortex that are different from the non-specific effects of sham stimulation. Significance: Our study reaffirms that TMS-EEG represents an effective tool to evaluate cortical neurophysiology with high fidelity.
AB - Objective: We measured the neurophysiological responses of both active and sham transcranial magnetic stimulation (TMS) for both single pulse (SP) and paired pulse (PP; long interval cortical inhibition (LICI)) paradigms using TMS-EEG (electroencephalography). Methods: Nineteen healthy subjects received active and sham (coil 90° tilted and touching the scalp) SP and PP TMS over the left dorsolateral prefrontal cortex (DLPFC). We measured excitability through SP TMS and inhibition (i.e., cortical inhibition (CI)) through PP TMS. Results: Cortical excitability indexed by area under the curve (AUC(25-275ms)) was significantly higher in the active compared to sham stimulation (F(1,18) = 43.737, p < 0.001, η2 = 0.708). Moreover, the amplitude of N100-P200 complex was significantly larger (F(1,18) = 9.118, p < 0.01, η2 = 0.336) with active stimulation (10.38 ± 9.576 µV) compared to sham (4.295 ± 2.323 µV). Significant interaction effects were also observed between active and sham stimulation for both the SP and PP (i.e., LICI) cortical responses. Finally, only active stimulation (CI = 0.64 ± 0.23, p < 0.001) resulted in significant cortical inhibition. Conclusion: The significant differences between active and sham stimulation in both excitatory and inhibitory neurophysiological responses showed that active stimulation elicits responses from the cortex that are different from the non-specific effects of sham stimulation. Significance: Our study reaffirms that TMS-EEG represents an effective tool to evaluate cortical neurophysiology with high fidelity.
KW - Long interval cortical inhibition
KW - Sham TMS
KW - TMS-EEG
KW - TMS-evoked potential
UR - http://www.scopus.com/inward/record.url?scp=85108013066&partnerID=8YFLogxK
U2 - 10.1016/j.clinph.2021.05.009
DO - 10.1016/j.clinph.2021.05.009
M3 - Article
C2 - 34147010
AN - SCOPUS:85108013066
VL - 132
SP - 1850
EP - 1858
JO - Clinical Neurophysiology
JF - Clinical Neurophysiology
SN - 1388-2457
IS - 8
ER -