Altered motor system function in post-concussion syndrome as assessed via transcranial magnetic stimulation.

Abstract

OBJECTIVE:

It is unclear why specific individuals incur chronic symptoms following a concussion. This exploratory research aims to identify and characterize any neurophysiological differences that may exist in motor cortex function in post-concussion syndrome (PCS).

METHODS:

Fifteen adults with PCS and 13 healthy, non-injured adults were tested. All participants completed symptom questionnaires, and transcranial magnetic stimulation (TMS) was used to measure intracortical and transcallosal excitability and inhibition in the dominant motor cortex.

RESULTS:

Cortical silent period (p = 0.02, g = 0.96) and ipsilateral silent period (p = 0.04, g = 0.78) were shorter in the PCS group compared to the control group which may reflect reduced GABA-mediated inhibition in PCS. Furthermore, increased corticomotor excitability was observed in the left hemisphere but not the right hemisphere.

CONCLUSIONS:

These data suggest that persistent neurophysiological differences are present in those with PCS. The exact contributing factors to such changes remain to be investigated by future studies.

SIGNIFICANCE:

This study provides novel evidence of lasting neurophysiological changes in PCS.

• Authors: Mitchell B Locke, Stephen L Toepp, Claudia V Turco, Diana H Harasym, Michel P Rathbone, Michael D Noseworthy, Aimee J Nelson
• Journal: Clinical neurophysiology practice (Clin Neurophysiol Pract) Vol. 5 Pg. 157-164 ( 2020) ISSN: 2467-981X [Electronic] Netherlands
• PMID: 32939420 (Publication Type: Journal Article)
• Copyright: © 2020 International Federation of Clinical Neurophysiology. Published by Elsevier B.V.