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Title: Loss of consciousness, but not etiology, predicts better working memory performance years after concussion
Background: Patients with uncomplicated cases of concussion are thought to fully recover within several months as symptoms resolve. However, at the group level, undergraduates reporting a history of concussion (mean: 4.14 years post-injury) show lasting deficits in visual working memory performance. To clarify what predicts long-term visual working memory outcomes given heterogeneous performance across group members, we investigated factors surrounding the injury, including gender, number of mild traumatic brain injuries, time since mild traumatic brain injury (mTBI), loss of consciousness (LOC) (yes, no), and mTBI etiology (non-sport, team sport, high impact sport, and individual sport). We also collected low-density resting state electroencephalogram to test whether spectral power was correlated with performance. Aim: The purpose of this study was to identify predictors for poor visual working memory outcomes in current undergraduates with a history of concussion. Methods: Participants provided a brief history of their injury and symptoms. Participants also completed an experimental visual working memory task. Finally, low-density resting-state electroencephalogram was collected. Results: The key observation was that LOC at the time of injury predicted superior visual working memory years later. In contrast, visual working memory performance was not predicted by other factors, including etiology, high impact sports, or electroencephalogram spectral power. Conclusions: Visual working more » memory deficits are apparent at the group level in current undergraduates with a history of concussion. LOC at the time of concussion predicts less impaired visual working memory performance, whereas no significant links were associated with other factors. One interpretation is that after LOC, patients are more likely to seek medical advice than without LOC. Relevance for patients: Concussion is a head injury associated with future cognitive changes in some people. Concussion should be taken seriously, and medical treatment sought whenever a head injury occurs. « less
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Journal of Clinical and Translational Research
Sponsoring Org:
National Science Foundation
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