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Thesis Format

Integrated Article


Master of Science




Christie, Anita D.


The purpose of this study was to examine potential sex-related differences in neurophysiology in concussed and healthy individuals. There was a total of 21(9 F) participants in each group. The concussion (CONC) group reported to the lab within 72 hours, 1- and 2-weeks post-injury. The control (CONT) group followed a similar measurement schedule once recruited. Motor evoked potential (MEP) amplitude and cortical silent period (CSP) duration was measured in the first dorsal interosseous muscle using transcranial magnetic stimulation. There were no significant differences in MEP amplitude or CSP duration between the CONC and CONT group. As well, there was no significant effect of time on these cortical measures. However, males had significantly longer CSP durations compared to females, indicating greater cortical inhibition, regardless of group. An important and novel finding of this study was the lack of differences in these neurophysiological measures between males and females following concussion.

Summary for Lay Audience

Brain excitability and inhibition can be affected by the chemical changes that occur post-concussion. Research currently demonstrates that brain excitability is generally the same between concussed and healthy individuals. However, it has been reported that concussed individuals have greater brain inhibition levels than healthy individuals, but these measures have not been examined between sexes. Therefore, the purpose of this study was to determine potential sex-related differences in brain activity post-concussion. Twenty-one (9 F) concussed and healthy control individuals were recruited to come into the lab 72 hours post-concussion, and again at 1- and 2-weeks post-injury. Communication between the brain and muscle was measured in a hand muscle using transcranial magnetic stimulation. I did not find any differences in brain excitability or inhibition between the concussion group and the healthy control group. As well, these measures did not change over the 2-week testing period. Overall, males had significantly greater brain inhibition levels compared to females, regardless of injury status. This was the first study to demonstrate no differences in brain excitability or inhibition between males and females due to concussion.

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Creative Commons Attribution 4.0 License
This work is licensed under a Creative Commons Attribution 4.0 License.