Eye Tests Detect Long-Term Brain Changes After Concussion in Veterans

Even years after the visible wounds have healed, the effects of a concussion can linger, subtly altering brain function. Modern research from the University of Colorado Anschutz Marcus Institute for Brain Health suggests that veterans who experienced concussions may exhibit measurable differences in brain activity more than a decade after the initial injury. These changes, detected through specialized high-speed eye movement testing, offer a potential new avenue for understanding and addressing the long-term consequences of mild traumatic brain injury (mTBI).

The Eyes as a Window to Brain Health

Mild traumatic brain injuries, commonly occurring in military service, athletes, and civilians due to impacts from sports, accidents, or falls, often resolve within weeks or months. However, this study, published in the Journal of Neuro-Ophthalmology, indicates that some individuals may experience lasting alterations in attention, processing speed, and impulse control. The research team, led by Jeffrey Hebert, Ph.D., PT, focused on the connection between eye movements and underlying brain function.

“The eyes are directly connected to brain networks that control attention, information processing, and decision-making,” explains Dr. Hebert, associate professor at the CU Anschutz School of Medicine and director of research for the CU Anschutz Marcus Institute for Brain Health. “By studying how someone’s eyes move during a cognitively demanding task, we can detect subtle brain changes that might not appear on a standard bedside exam or brain scan.”

The study involved 78 military veterans – 38 with a history of mTBI and 40 without. Participants underwent a series of eye movement tests alongside cognitive assessments designed to measure executive functions like attention, processing speed, and self-control. Researchers discovered that veterans with a history of concussion tended to have slower and less accurate eye movements, coupled with reduced performance on attention-based tasks. Notably, some of these differences remained detectable more than ten years after the original injury.

Eye movements are a complex process, relying on interconnected networks across multiple brain regions. Tasks requiring rapid shifts in gaze, or quick visual recognition and verbalization, test not only visual function but also cognitive control – the ability to focus, suppress impulses, and respond accurately. Dr. Hebert suggests that multiple mild injuries can leave lasting, yet difficult-to-detect, effects due to this widespread neural involvement. Cognitively demanding tasks are key to revealing these subtle changes.

“Even when someone feels recovered, their brain may still be working differently behind the scenes, especially during visually demanding tasks and in busy environments,” Dr. Hebert notes. “Objective eye movement testing gives us a measurable way to assess these often covert problems.”

Beyond the Battlefield: Implications for Concussion Care

The findings have significant implications for how concussions are managed long-term. Currently, standard imaging techniques like MRI scans often appear normal after a mild brain injury, making it challenging to objectively verify persistent symptoms. The researchers propose that incorporating cognitively challenging eye movement assessments could provide clinicians with an additional tool to better understand ongoing cognitive concerns and tailor rehabilitation strategies more effectively.

Even as the study focused on military veterans, the potential applications extend to athletes, first responders, and civilians who have experienced concussions. Eye tests reveal brain trauma more than a decade after the initial injury, according to the University of Colorado Anschutz.

The research team emphasizes that most individuals do recover well from mild traumatic brain injury. However, identifying those who continue to experience subtle effects could lead to improved follow-up care, long-term monitoring, and more targeted treatment planning, ultimately promoting healthier brain adaptation.

What’s Next for Concussion Assessment?

Future studies will investigate whether integrating cognitively challenging eye movement testing into routine concussion evaluations can help clinicians more accurately diagnose traumatic brain injury, track recovery progress, and guide treatment decisions. High-speed eye tests are showing promise in detecting these “invisible” brain injuries.

The team also plans to explore the potential of using eye tracking data to personalize rehabilitation programs, tailoring interventions to address specific cognitive deficits identified through the testing. This personalized approach could maximize recovery outcomes and improve the quality of life for individuals affected by long-term concussion symptoms.

For veterans, athletes, and anyone experiencing the aftermath of a concussion, staying informed about the latest research and seeking guidance from qualified healthcare professionals is crucial. A holistic approach to healing, as highlighted by the University of Colorado Anschutz, is essential for optimizing recovery and long-term well-being.