Concussion Tests: What They Measure, What They Miss, and When You Need More

Educational content from The Neural Connection. This article is for educational purposes only and is not a diagnosis or a substitute for individualized medical advice. If symptoms are persistent, worsening, or concerning, consult a qualified healthcare professional.

Medically reviewed by Dr. Erik Reis, DC, DACNB on September 16, 2026.

Clinicians use five main concussion tests, each for a different question: SCAT6 for sideline symptoms, ImPACT for cognitive tracking, the 22-item Post-Concussion Symptom Scale for self-reported burden, the Vestibular/Ocular Motor Screen for five vestibular and oculomotor pathways, and a functional neurological evaluation for all five systems. No single concussion test rules a concussion in or out. At The Neural Connection in the Twin Cities, that’s where it starts.

What each testing tool is designed to measure

Five testing frameworks handle distinct territory in concussion assessment. SCAT6 is the standardized sideline screen, covering symptom count, memory, concentration, and balance under field conditions. Computerized neurocognitive tests like ImPACT track reaction time, processing speed, and memory scores against a pre-injury baseline.

The Post-Concussion Symptom Scale is a 22-item self-report that quantifies symptom burden over time. The Vestibular/Ocular Motor Screen (VOMS) assesses five pathways (smooth pursuit, horizontal and vertical saccades, near point of convergence, vestibular-ocular reflex, and visual motion sensitivity) that these tools don’t formally evaluate. A functional neurological evaluation tests all of those systems and more, in a clinical setting, objectively and in isolation. Each tool was designed for a specific phase of assessment. None was built to replace the others.

Test	What it measures	Where it stops
SCAT6	Symptom count, memory, concentration, and balance under sideline conditions	No objective vestibular or oculomotor data; can be influenced by motivation and effort; normal result does not authorize return to activity
Computerized neurocognitive (e.g., ImPACT)	Reaction time, processing speed, memory relative to pre-injury baseline	Requires a valid pre-injury baseline to be individually interpretable; measures cognitive performance, not vestibular or oculomotor function
Post-Concussion Symptom Scale (PCSS)	22-item self-reported symptom burden including headache, dizziness, visual strain, and cognitive complaints	Self-reported only; symptoms can resolve before measurable neurological dysfunction does
Vestibular/Ocular Motor Screen (VOMS)	Five pathways: smooth pursuit, horizontal and vertical saccades, near point of convergence, vestibular-ocular reflex, and visual motion sensitivity	Brief clinical screen; identifies the presence of vestibular-ocular provocation, not its source or severity
Functional neurological evaluation	Vestibular function, oculomotor tracking, balance, cervical proprioception, and autonomic regulation, each tested objectively and in isolation	Identifies measurable functional deficits across systems; cannot predict recovery timeline or isolate a single cause for every symptom

Table 1. Five post-concussion assessment tools: what each measures and where each one stops.

Where the screening gap sits

Sideline tools like the SCAT6 and PCSS are designed for one job: rapid identification of a probable concussion at the point of injury or within the first days after. They do that job, and they do it without requiring clinical equipment. A Cleveland Clinic overview of concussion management describes the initial workup as covering acute assessment, imaging when indicated, and cognitive screening, which is an accurate account of what these tools were built to provide. The gap often shows up later as symptoms when a patient is two or three weeks out from an injury when the SCAT score has returned to baseline and symptoms have cleared on the PCSS.

And yet, something still feels off: difficulty tracking text across a screen, low-level dizziness in busy environments, visual discomfort with no clear explanation, or a persistent sense that concentration is working harder than it should.

We see this pattern regularly in the office. Patients often describe an evaluation history that moved quickly through symptom questionnaires and cognitive screens without formally testing the vestibular or oculomotor systems at all. The screening tool they received was appropriate for the phase it was designed for. The issue is that it wasn’t designed for the phase they’re in.

The research reflects this. A 2021 review in Frontiers in Neurology tracking neurophysiological outcomes after concussion found that up to 50% of patients still reported persistent post-concussive symptoms three months after injury, a period well past when most standardized screening is no longer applied. The screen did its job at the sideline. That doesn’t mean it’s the right instrument for explaining why vestibular and oculomotor function hasn’t settled.

A sideline screening tool functions like a smoke alarm, catching the signal that something dangerous is present and protecting you from the worst immediate outcomes, but it can’t locate which system is burning or tell you what will put it out. Computerized neurocognitive testing fills part of that gap for cognitive recovery, and it fills it well when there’s a pre-injury baseline to compare against. Without that baseline, individual interpretation becomes harder, since normal ranges vary considerably across ages and performance backgrounds. And even when cognitive scores normalize, they don’t tell you whether vestibular or oculomotor pathways have returned to their pre-injury state, because those systems aren’t what those tools measure.

What the VOMS found that standard screening missed

One of the better-documented gaps in standard post-concussion screening involves the vestibular and oculomotor systems, pathways that the SCAT6 and PCSS don’t formally evaluate. In 2014, Mucha and colleagues published a validation study for the Vestibular/Ocular Motor Screen in the American Journal of Sports Medicine. The study enrolled 64 patients seen approximately five days after a sport-related concussion and 78 healthy controls.

The findings were specific: 61% of the concussed patients reported symptom provocation on at least one of the five VOMS components. The vestibular-ocular reflex component carried an odds ratio of 3.89 for identifying concussion, and visual motion sensitivity carried an odds ratio of 3.37. The combined model, incorporating the vestibular-ocular reflex, visual motion sensitivity, near point of convergence distance, and age, produced an area under the curve of 0.89 for discriminating concussed from non-concussed patients.

That’s meaningful discriminative ability from a five-minute screen, and in a population where standard symptom scores had already been collected. The vestibular-ocular reflex and visual motion sensitivity components, the two most predictive, are not evaluated by the SCAT6 or any standard cognitive battery.

The VOMS is not a comprehensive functional evaluation. It identifies the presence and approximate location of vestibular-ocular provocation across five specific pathways. It doesn’t measure the source of the dysfunction, quantify severity across a full spectrum of balance and cervical function, or produce the system-by-system map that guides targeted rehabilitation. But it fills a gap that the standard screening battery doesn’t address, in a clinical format that takes about five minutes.

When symptoms outlast a normal result

A normal result at day 10 or day 14 doesn’t confirm that the vestibular and oculomotor systems have returned to baseline. A 2019 study in the Journal of Science and Medicine in Sport found that 59% of concussed patients showed vestibular-ocular impairment within 10 days of injury, and that among those initially impaired, recovery times averaged 12 days longer than in those without early vestibular involvement. That’s a clinically meaningful difference, and it’s driven by systems that don’t appear on standard cognitive tests or symptom scales.

The gap between symptom resolution and functional recovery is where a full functional neurological evaluation becomes relevant. A patient who scores normally on a symptom scale may still have measurable deficits in smooth pursuit accuracy, near-point convergence, or head repositioning accuracy. Those deficits can be clinically meaningful regardless of whether they’re showing up in self-reported symptoms, because functional impairment and subjective symptom load don’t always track together after a concussion.

At The Neural Connection in the Twin Cities, a functional neurological evaluation tests each of those systems in isolation, specifically to find the ones that haven’t normalized when everything else on paper says clear. The evaluation includes videonystagmography (VNG) for objective eye movement analysis, computerized balance testing under varied sensory conditions, and cervical proprioception assessment, among others. Patients who’ve had prior evaluations that returned normal results often describe the first visit as the point where the clinical picture finally matched what they’d been experiencing.

Post-concussion care at The Neural Connection is built around what objective functional testing reveals, not around what a symptom scale cleared. For patients weighing whether to pursue further evaluation, our article on what happens when concussion symptoms aren’t addressed covers the longer-term trajectory.

When to seek urgent care

Most of what brings someone to a post-concussion evaluation is not an emergency. The danger signs that require immediate attention point to acute structural, vascular, or neurological problems, which are different in character from the functional post-concussive presentations a clinical evaluation is designed to address.

Go to the ER or call 911 right away. Don’t wait for a phone consult if you develop any of the following after a head or neck injury:

• A headache that is severe, worsening, or “the worst headache of your life”
• Weakness, numbness, tingling, poor coordination, or trouble walking
• Slurred speech or trouble speaking
• Repeated vomiting
• Fainting, loss of consciousness, extreme drowsiness, or trouble waking up
• A seizure
• New or worsening confusion, unusual behavior, agitation, or not recognizing people or places
• Vision loss, double vision, or one pupil larger than the other
• Chest pain or shortness of breath
• Severe or rapidly worsening neck pain, especially after trauma
• Blood or clear fluid from the nose or ears, or concern for a skull fracture

Frequently asked questions (FAQ)

What is a concussion test?

Standardized post-concussion assessment covers several distinct tools, each measuring something different. The SCAT6 screens symptom count, balance, and basic cognitive function at the sideline. Computerized tools like ImPACT compare cognitive performance against a pre-injury baseline. The Post-Concussion Symptom Scale tracks 22-item self-reported burden over time. The VOMS screens vestibular and oculomotor pathways across five components. A functional neurological evaluation tests all of those systems objectively and in isolation, at a level of specificity that a screening tool isn’t designed to reach. No single tool covers the full range of how a concussion can affect the nervous system.

Can screening results be normal even when a concussion is still affecting you?

Yes. These tools measure specific things, and what they measure can normalize while other systems haven’t. Cognitive scores may return to baseline and symptom questionnaires may clear while vestibular or oculomotor deficits remain present and measurable. A 2019 study found that 59% of concussed patients showed vestibular-ocular impairment within 10 days of injury, in a population that included patients who were otherwise progressing normally on standard measures. A normal screening result is meaningful information. It isn’t the same as confirmation that every system has returned to its pre-injury state.

How accurate is ImPACT and other computerized post-injury testing?

Computerized neurocognitive tests like ImPACT are well-validated for what they measure: changes in cognitive performance, processing speed, and reaction time relative to a pre-injury baseline. Their accuracy depends heavily on having a valid pre-injury baseline for comparison, since individual performance varies considerably across age groups and athletic populations. They’re useful for tracking the cognitive arc of recovery, particularly in a return-to-sport context. They don’t measure vestibular function, oculomotor tracking, or cervical proprioception, so a normal computerized test result doesn’t tell you whether those systems have recovered.

What does testing at a functional neurology clinic look like?

A full functional neurological evaluation tests vestibular function, oculomotor tracking, balance under varied sensory conditions, cervical proprioception, and autonomic regulation, each in isolation. The specific tools include videonystagmography (VNG) for objective eye movement analysis, computerized balance testing, and a detailed intake covering the full symptom and evaluation history. The appointment runs 60 to 90 minutes and ends with a clinical map showing which systems tested outside of expected ranges and a rehabilitation plan targeting those specific deficits. It’s a different clinical question than a screening tool is built to answer.

How long after a concussion should you get tested?

Different tools are used at different points in the recovery process. The SCAT6 is designed for immediate sideline use. ImPACT and the PCSS are typically administered within the first days and tracked serially across recovery. The VOMS is most informative in the early weeks following injury. A functional neurological evaluation is relevant at any point when symptoms persist beyond expected recovery timelines. Patients who’ve had clean screenings and are still symptomatic at six weeks, three months, or beyond are the clearest candidates, though earlier evaluation is appropriate when vestibular or oculomotor involvement is suspected from the start.

When does post-concussion screening stop being enough?

Post-concussion screening is a monitoring tool, not a comprehensive diagnostic evaluation, and there’s no single test that definitively confirms or rules out a concussion. When symptoms outlast the normal recovery window, which for most concussions resolves within days to a few weeks, a screening result that came back normal isn’t a verdict on what’s still happening. Persistent headache, dizziness, visual strain, and cognitive fog at four weeks or later point to systems that may not have been formally evaluated yet. That’s the territory post-concussion care structured around functional findings is built to address, and it’s where a screening-only approach most often leaves patients without answers.

For patients throughout the Twin Cities and greater Minnesota who’ve received a normal screening result but haven’t fully recovered, a functional neurological evaluation is often where the clinical findings come together for the first time. The Neural Connection provides comprehensive functional neurological evaluations for patients across the Twin Cities and greater Minnesota.

*Note: The information provided in this article is for educational purposes only and does not constitute a doctor-patient relationship. Patients are advised to consult their medical provider or primary care physician before trying any remedies or therapies at home.