Follow the Finger: How Eye Tracking and Objective Testing Help Identify Concussions

From Manual to Machine: The Rise of Objective Eye-Tracking

While traditional oculomotor exams provide valuable insight, they are inherently subjective. 

Clinician experience, patient cooperation, and environmental variables all influence the outcome. Enter eye-tracking technology—an objective, automated tool that adds precision to what has historically been a qualitative exam.

Another study published in the Journal of Neurotrauma introduced a novel eye-tracking method that does not rely on spatial calibration (i.e., asking subjects to follow dots on a screen). Instead, the approach uses non-spatial calibration by tracking spontaneous eye movements while subjects passively watch short videos. This method has demonstrated the ability to detect abnormal eye movements within hours of a concussion and to track recovery over several weeks—without requiring active participation or intact vision (PMC4590232).

This is particularly impactful in pediatric populations, uncooperative patients, or individuals experiencing acute symptoms who may not be able to follow standard test procedures. The technology also offers the potential to quantify concussion severity and provide a reliable marker for when oculomotor function returns to baseline—key in informing return-to-play decisions.

Clinical Reliability and Limitations: What the Research Says

A recent review of existing literature on eye movement as a biomarker for mTBI underscores both the promise and the challenges of this approach. Published in 2022, the review examined various ocular metrics, including saccades, smooth pursuit, vergence, and pupil response. It found that cognitively demanding saccade tasks (like anti-saccades or memory-guided movements) consistently showed impairment in individuals with mTBI. These impairments were linked to prolonged reaction times, accuracy errors, and increased positional deviations (PMC9682364).

However, the review also noted inconsistencies across studies—largely due to methodological variability, differing eye-tracking devices, and inconsistent protocols. 

Basic reflexive eye movements (like simple saccades) were less sensitive to concussion-related changes, which means relying on isolated metrics may not be enough. Standardization of testing methods, sampling rates, and calibration protocols is still needed before eye tracking can be broadly adopted as a clinical diagnostic benchmark.

Despite these limitations, the utility of eye movement analysis is clear when used as part of a multimodal assessment strategy—particularly when integrated with patient symptom profiles, cognitive testing, and vestibular evaluations.

Real-World Application: From Sidelines to Clinics

For athletic trainers and sports medicine clinicians, eye-tracking tools can serve as an efficient and reliable addition to their current concussion management protocols. On the sidelines, subjective “follow the finger” tasks remain crucial for initial evaluations—especially when time and resources are limited. But when athletes return to the clinic, adding objective eye-tracking data enhances diagnostic accuracy and helps monitor recovery progress over time.

Consider a college athletic trainer working with high-performance soccer athletes. Imagine a situation where, five days post-impact, a player is still experiencing headaches and a sense of slowed thinking. Standard symptom checklists appear stable, yet the VOMS assessment continues to show difficulty with smooth pursuit and convergence. In this scenario, the athletic trainer might refer the athlete for an eye-tracking evaluation, which could reveal lingering oculomotor abnormalities. This additional layer of objective data would support a more cautious return-to-play timeline and highlight the importance of comprehensive evaluation in guiding recovery.

These cases aren’t uncommon. Persistent concussion symptoms—ranging from dizziness and visual strain to brain fog—often involve some component of oculomotor dysfunction. Catching these early with “follow the finger” exams or validated eye-tracking technology can reduce the risk of re-injury and promote more tailored rehabilitation strategies.

The Role of Physical Therapy and Vestibular Rehab

Physical therapists, especially those specializing in vestibular and concussion rehabilitation, play a key role in treating the downstream effects of oculomotor dysfunction. Rehabilitation may include:

• Gaze stabilization exercises to retrain smooth pursuit and saccadic function.
• Dynamic visual acuity training to improve eye-head coordination.
• Vergence therapy to address visual convergence insufficiencies contributing to headaches and visual fatigue.

By combining therapeutic intervention with objective testing tools, PTs can track progress in a quantifiable way. This not only supports clinical decision-making but also provides concrete feedback to patients and referral sources.

Many therapists report that when eye-tracking results are shared visually with athletes or parents, compliance with rehab dramatically improves. Seeing the evidence—whether it’s a scattered gaze path or delayed saccade—makes the invisible injury feel more real and more actionable.

Looking Forward: A More Objective Future in Concussion Care

The path to standardized concussion diagnosis has always been complex. But eye movement testing—especially when enhanced by eye-tracking technology—is providing clearer clinical markers to identify and monitor brain function after injury. Tools like the “follow the finger” test, once considered too basic to carry weight, are now backed by imaging studies and neurophysiological data that prove their value.

As technology evolves and testing protocols become more refined, we can expect broader integration of eye-tracking in sideline evaluations, clinic-based screenings, and even telehealth concussion care. For now, combining traditional exams with emerging technology offers a balanced, evidence-informed approach to identifying and managing concussions more effectively.

For athletic trainers, physical therapists, and sports medicine professionals, staying ahead means embracing tools that are both rooted in science and practical in everyday care. If you’re interested in how objective testing can complement your current protocols—or if you’re seeking ways to streamline concussion assessment and recovery—consider exploring technologies like Sway. 

Our goal is to empower your clinical expertise with tools that make your job easier, safer, and more precise.