Differential Sensitivity of ImPACT and VR Testing Modalities in Assessment of Concussion: An EEG Study

Open Access
Teel, Elizabeth Fay
Graduate Program:
Master of Science
Document Type:
Master Thesis
Date of Defense:
May 06, 2013
Committee Members:
  • Semyon Slobounov, Thesis Advisor
  • William Ray, Thesis Advisor
  • Peter Andrew Arnett, Thesis Advisor
  • David E Conroy, Thesis Advisor
  • Concussion
  • EEG
  • ImPACT
  • VR
  • Sensitivity
  • Reproducibility
While concussions are defined as a pathophysiological injury, clinical paradigms for concussion management focus solely on the resulting functional deficits and ignore the underlying physiology. The clinical standard of neuropsychological testing, balance evaluations, and symptom checklists is highly sensitive, but there is no indication that the resolution of functionality corresponds to the resolution of the physiologic injury. EEG is a valuable research and clinical tool capable of directly assessing physiological processes in a concussed brain. The primary purpose of this study was to evaluate differences in EEG power and coherence between a concussed and control group performing ImPACT testing and VR balance and spatial modules. A secondary purpose was to examine the reproducibility of ImPACT and VR testing. VR Stationary Score was significantly (p=.026) lower in the concussed group, but no other ImPACT or VR variable reached significance. The concussed group had lower EEG power (p<.05) over all testing measures. The concussed group also had significantly (p<.05) altered communication pathways seen via coherence differences. ImPACT’s Motor Speed and Reaction Time Composites and VR’s Roll Score, Head Motion, and Spatial Time Back were all found to be highly reproducible (ICC>0.70). All other outcome measure displayed moderate to low levels of reproducibility. Overall, the major findings show that concussed individuals who are clinically asymptomatic continue to suffer from altered brain physiology. This should be considered when making return-to-play decisions for the athlete in order to protect his/her safety.