Researcher Examines the Risks and Consequences of Mild Concussions in Veterans and Athletes

Key Findings

  • Pre-injury psychosocial factors affect recovery following mild traumatic brain injury (mTBI) in athletes and veterans.
  • Better cognitive functioning before a concussion has been associated with less severe symptoms following a concussion.
  • The APOE e4 allele that is associated with Alzheimer’s disease has been associated with poorer clinical outcomes following mild traumatic brain injury (mTBI).

FABBS is delighted to name Dr. Victoria Merritt an early career impact award winner for her contributions in understanding the genetic, neuropsychological, and clinical components of Mild traumatic brain injuries in multiple populations. Mild traumatic brain injuries (mTBIs), also known as concussions, are a substantial health concern to both veterans and athletes due to their frequency and potential impact on both physical and mental health. Improving understanding of the risks and consequences of mTBI is therefore a national research priority. 

Dr. Merritt obtained her Ph.D. in clinical psychology from The Pennsylvania State University and is currently an Assistant Professor in the Department of Psychiatry at the University of California San Diego (UC San Diego) and a Research Health Scientist at the VA San Diego Healthcare System (VASDHS). She is also a member of the National Academy of Neuropsychology, her nominating society, in addition to several other professional societies. In a recent interview, Dr. Merritt spoke with FABBS about the importance of her research for athletes and veterans alike.   

Dr. Merritt’s interest in neuropsychology and mTBI research began when she was a research assistant at Walter Reed Army Medical Center in Washington, D.C. Her experiences at Walter Reed inspired her to study neuropsychology in graduate school, where she joined Penn State’s Clinical Psychology PhD program. During her tenure at Penn State, she was involved in the Neuropsychology of Sports Concussion Program, a clinical research program offering baseline and post-concussion neuropsychological testing to Penn State Division 1 athletes. Dr. Merritt conducted neuropsychological testing for athletes before athletic seasons started, as well as after athletes sustained concussions. She interpreted changes in performance from baseline to post-concussion testing and wrote clinical reports using this data, ultimately sharing this information with team trainers and physicians to assist them in making return to play decisions for the concussed athletes. This translational work had an immediate impact on the well-being of athletes and highlights the potential of neuropsychological services in addressing issues prevalent at all levels of athletics.

Further leveraging this clinical research program, Dr. Merritt engaged in multiple studies of how pre-concussion factors may impact post-concussion outcomes. A key finding from her master’s thesis was that baseline neurocognitive performance was associated with symptom endorsement patterns following a concussion, such that better cognitive scores at baseline predicted lower symptom scores after concussion. For her dissertation, she examined the extent to which genetic factors influence neuropsychological outcomes after a concussion. She found that the APOE e4 allele, a variant associated with risk for Alzheimer’s disease, was also associated with worse post-concussion symptoms and cognitive outcomes after sustaining a concussion in college athletes. This novel finding suggested there may be innate biological traits that leave individuals more vulnerable to poor outcomes following a concussion. Though these findings were compelling, Dr. Merritt noted two challenges. First, reliable inferences about genetic vulnerabilities required much larger samples, and second, the discovery of a potential genetic association led to many new questions about the underlying mechanisms that could explain this association.

Dr. Merritt is currently addressing these challenges with her research at VASDHS. Described as her dream project, she is using the VA Million Veteran Program (MVP) to study the influence of genetics on neuropsychological and neurobehavioral outcomes in hundreds of thousands of veterans with a history of TBI. She and her team recently published the first genome-wide association study (GWAS) of TBI using MVP data. This research identified many significant genes, including APOE, and revealed high genetic correlations between TBI and psychiatric and risk-taking traits, significantly advancing our understanding of the genetic basis of TBI. These findings bolster her prior research and provide further confidence in there being genetic factors associated with TBI.

The next step for Dr. Merritt is studying how genetics influence outcome and recovery following TBI. She has identified the existence of a gene-environment interaction, but the actual mechanism is still under investigation. Dr. Merritt plans to continue this line of study and was recently awarded a large grant through the VA to pursue ongoing research pertaining to the genetics of TBI in the veteran population. Ultimately, she hopes this research can lead to the identification of possible targets for pharmaceutical treatments as well as the identification of characteristics that promote recovery following injury.

In addition to her translational research, Dr. Merritt engages in numerous service projects on a local and national level. For example, she works to improve the connection between her workplace and the community through diversity, equity, and inclusion initiatives. One specific project she was involved in was identifying the underserved members of her community and addressing barriers to their care. She also volunteers on several committees for various professional organizations and mentors students at all levels of their professional training. 

Future Directions

  • Predicting when it is safe for athletes to return to their sport after concussion.
  • Identifying biological, psychological, and sociodemographic factors that are associated with clinical outcomes following mTBI.
  • Identifying treatment targets using precision medicine.

2023 Eca Nan Merritt Headshot

Dr. Victoria Merritt is a recipient of the 2023 Federation of Associations in Behavioral & Brain Sciences (FABBS) Early Career Impact Award and was nominated by The National Academy of Neuropsychology.

The 43rd annual NAN conference, The Future of Brain Health Science and Applications, takes place in Philadelphia, Pennsylvania, from October 25-28, 2023.

Read more about Dr. Merritt’s work at the links below: