Genetic Factors and Neuropsychological Outcome Following Sports-Related Concussion

Restricted (Penn State Only)
Merritt, Victoria C
Graduate Program:
Doctor of Philosophy
Document Type:
Date of Defense:
April 25, 2016
Committee Members:
  • Peter A. Arnett, Dissertation Advisor
  • Peter A. Arnett, Committee Chair
  • Frank G. Hillary , Committee Member
  • Michael D. Shapiro, Committee Member
  • Semyon M. Slobounov, Outside Member
  • genetics
  • APOE
  • sports concussion
  • mild traumatic brain injury
  • college athletes
  • post-concussion symptoms
  • neurocognitive functioning
Over the past several years, sports-related concussion has become a topic of increasing interest and many efforts have been made to study not only the consequences of the injury, but also to more specifically understand the factors that contribute to the heterogeneity in recovery rates and outcome following concussion. Many studies have hypothesized a variety of possibilities to account for this observed heterogeneity, but few studies have addressed the role of genetics. There is some evidence in the broader traumatic brain injury (TBI) literature to suggest that the ϵ4 allele of the apolipoprotein E (APOE) gene may be linked to unfavorable outcome following brain injury, but this relationship has not been carefully explored in the context of sports concussion. The purpose of this dissertation was to examine whether the APOE gene influences neuropsychological outcomes following sports-related concussion in collegiate athletes. Having knowledge of potential risk factors that are associated with brain injury outcome has significant implications for athletes’ safety and well-being and could facilitate the development of safer and more efficient return to play guidelines. Three empirical studies were conducted, each focusing on a unique aspect critical to the assessment and evaluation of sports-related concussion. Paper 1 examined the relationship between the APOE ϵ4 allele and post-concussion symptom reporting. Paper 2 evaluated the extent to which the ϵ4 allele is associated with the presence and severity of headache in concussed and non-concussed athletes. Paper 3 studied neurocognitive functioning in concussed athletes to determine whether athletes with and without an ϵ4 allele differ in their neurocognitive profiles. The general hypothesis for the dissertation was that having an ϵ4 allele would be associated with increased symptom-reporting and poorer neurocognitive functioning following concussion.