Chronic Neurophysiological Effects of Repeated Head Trauma in Retired Australian Male Sport Athletes

Frontiers in Neurology

Michael E. Buckland¹  Alan J. Pearce²  Billymo Rist²  Mark A. Tommerdahl³  Rowena Mobbs⁵  Dawson J. Kidgell⁷  Ashlyn K. Frazer⁷  Jennifer Batchelor⁸ 

[1] Brain and Mind Centre, University Sydney, Camperdown, NSW, Australia;College of Science, Health and Engineering, La Trobe University, Melbourne, VIC, Australia;Cortical Metrics, Carrboro, NC, United States;Department of Biomedical Engineering, University of North Carolina, Chappell Hill, NC, United States;Department of Neurology, Macquarie University Hospital, Macquarie University, Sydney, NSW, Australia;Department of Neuropathology, Royal Prince Alfred Hospital, Sydney, NSW, Australia;Department of Physiotherapy, Faculty of Medicine Nursing and Health Science, Monash University, Melbourne, VIC, Australia;Department of Psychology, Macquarie University, Sydney, NSW, Australia;

关键词: concussion;    sports;    transcranial magnetic stimulation;    somatosensory;    mental fatigue;    motor cortex;   

DOI  :  10.3389/fneur.2021.633320

来源: DOAJ

【 摘 要 】

Aim: This study investigated the somatosensory and corticomotor physiology of retired contact sport athletes with a history of repeated concussion/subconcussion head trauma.Methods: Retired male athletes with a history of playing contact sports and repeated head trauma (n = 122) were divided into two groups: those who expressed concerns regarding their mental and cognitive health (“symptomatic”: n = 83), and those who did not express any ongoing concerns (“asymptomatic”: n = 39). Both groups were compared to age-matched male controls (n = 50) with no history of concussions or participation in contact sports, an absence of self-reported cognitive, or mood impairments. Transcranial magnetic stimulation (TMS) and vibrotactile stimulation were used to assess corticomotor and somatosensory pathways respectively. TMS and vibrotactile stimulation were correlated to self-reported responses using the Fatigue and Related Symptom Survey. Linear regression was used to associate concussion history with TMS, somatosensory variables.Results: Significant differences were found in symptom survey scores between all groups (p < 0.001). TMS showed significant differences between the “symptomatic” and control groups for intracortical inhibition and paired pulse TMS measures. Somatosensory measures showed significant differences for reaction time (p < 0.01) and reaction time variability (p < 0.01) between the “symptomatic” group to the “asymptomatic” and control groups. For other somatosensory measures, the “symptomatic” measures showed differences to the “control” group. Correlations showed significant associations between severity of symptom reporting with TMS and somatosensory measure, and regression revealed the number of concussions reported was shown to have significant relationships to increased intracortical inhibition and poorer somatosensory performance.Conclusion: This study shows that retired contact sport athletes expressing chronic symptoms showed significant pathophysiology compared to those with no ongoing concerns and non-concussed controls. Further, there is a linear dose-response relationship between number of reported concussions and abnormal neurophysiology. Neurophysiological assessments such as TMS and somatosensory measures represent useful and objective biomarkers to assess cortical impairments and progression of neuropsychological impairment in individuals with a history of repeated head trauma.

【 授权许可】

Unknown