Corticomotor correlates of somatosensory reaction time and variability in individuals with post concussion symptoms

• Published in: Somatosensory & motor research 2020-01, Vol.37 (1), p.14-21
• Main Authors: Pearce, Alan J., Kidgell, Dawson J., Frazer, Ashlyn K., King, Doug A., Buckland, Michael E., Tommerdahl, Mark
• Format: Article
• Language: English
• Subjects: Concussion; somatosensory reaction time; transcranial magnetic stimulation; visuomotor reaction time
• ISSN: 0899-0220; 1369-1651
• DOI: 10.1080/08990220.2019.1699045

Persistent post concussion symptoms (PPCS) describe the condition when an individual experiences chronic symptoms, particularly fatigue, beyond the expected time of recovery. The aim of this study was to quantify the effect of fatigue and related ongoing symptoms on somatosensory and corticomotor pathways using reaction time (RT) testing, and single-pulse and paired-pulse transcranial magnetic stimulation (TMS). Eighty-three participants (nine female, mean age 37.9 ± 11.5 years) were divided into two groups (persistent symptoms versus asymptomatic) following self-report based upon previously published clinical symptom scores. All participants completed somatosensory and visuomotor RT testing, as well as corticomotor excitability and inhibition measurements via TMS. Participants in the persistent symptom group (n = 38) reported greater number of previous concussions (t = 2.81, p = 0.006) and significantly higher levels of fatigue and related symptoms in the asymptomatic group (n = 45; t = 11.32, p