Exercise Biases Cognitive Performance and EEG Measures Used for Concussion Assessments

Objective: Determine the degree to which acute moderate exercise impacts performance in several concussion assessment tools and electrocortical measures of cognitive function used in the detection of concussion. Background: The effects of acute exercise on cognitive function are dependent on a number of factors, including the assessment type, exercise intensity, and recovery time before testing. Recently, emphasis is being placed on using cognitive assessment tools before and after injury in athletes, however little empirical evidence exists on the influence of exercise on these Methods: A gender-balanced cohort (N=8 /gender) was assessed with a single channel telemetric EEG recording device and cognitive test battery (Cerora Borealis, Cerora Inc.) immediately before and after moderate exercise (1-mile run). Heart rate and arterial oxygen levels were collected to control for the level of exertion. Results: We provide novel evidence that moderate exercise modestly improves performance on the King-Devick neuro-ophthalmologic saccade test (43.94+/-2.23 to 39.875+/-1.62 (mean+/-SEM total time(sec), Wilcoxon p = 0.0044) and standardized assessment of concussion (SAC) tool (27.9+/-0.43 to 29.125+/-0.26 mean(sec)+/-SEM, Wilcoxon p = 0.0039). During standard EEG recording methodology (bouts of quiet resting with eyes open or eyes closed) activity within the Theta band (4-8Hz) was decreased. However during the working memory component of the SAC, exercise produced a complex array of changes in EEG activity. Surprisingly, the majority of these effects were dependent on gender. Conclusions: Exercise can impact outcome measures of cognitive tests and direct measures of brain function used to identify concussion that may lead to biases in the interpretation of post-injury assessment measures. Although these observations are from a limited sample size, these findings which include evidence that gender plays an important role in the actions of exercise in these measures, indicate that further research is needed into the factors influencing outcome measures of these tests. Disclosure: Dr. Martino has nothing to disclose. Dr. Devilbiss has received personal compensation for activities with NexStepBiomarkers LLC and Cerora, Inc. as an owner. Dr. Etnoyer-Slaski has nothing to disclose. Dr. Simon has received personal compensation for activities with Cerora, Inc. as an owner, director, officer, and employee.