Clinical Tools
Neurocognitive Testing in TBI
Computerised and paper-based neurocognitive tests measure the cognitive effects of brain injury — but their dependence on baseline scores, patient effort, and practice effects limits their reliability as standalone diagnostic tools. Objective biomarkers provide the missing biological anchor.
What Is Neurocognitive Testing?
Neurocognitive testing evaluates the functional impact of brain injury on cognitive domains including memory, attention, processing speed, reaction time, and executive function. In the context of TBI and mTBI/concussion, these tests are used to detect cognitive impairment at the time of injury, track recovery over time, and inform RTP and RTD decisions. Testing duration varies according to the neurocognitive battery and assessment protocol used.
Computerised neurocognitive tests — including ImPACT, Cogstate, ANAM, and Axon Sports — have become standard in elite sport and military medicine over the past two decades. Their key advantage over symptom-based tools is that they generate objective performance data: reaction times, accuracy scores, and composite indices that can be compared against a pre-injury baseline or normative population data. However, this objectivity is conditional — it depends on the quality of the baseline, the effort of the test-taker, and the absence of confounding factors that affect cognitive performance independently of brain injury.
Neurocognitive Testing: The Evidence
No baseline
available for the vast majority of TBI patients outside elite sport and military programmes — limiting individualised interpretation
Effort
dependent — a motivated test-taker may perform within normal limits despite underlying neurological injury, particularly in the acute phase
Practice
effects inflate scores on serial testing — complicating recovery monitoring and RTA decisions
Cognitive
performance reflects many factors beyond brain injury — anxiety, fatigue, sleep, and medication all confound results
The Diagnostic Gap
Where Neurocognitive Tests Fall Short
The fundamental limitation of neurocognitive testing is that it measures cognitive performance — not brain injury. A motivated athlete or service member may perform within normal limits on a neurocognitive battery despite underlying neurological injury, particularly in the acute phase when adrenaline and competitive drive can temporarily mask impairment. Conversely, anxiety, fatigue, sleep deprivation, pre-existing learning disabilities, and medication effects can all depress performance in the absence of brain injury, producing false-positive results.
Baseline testing — the cornerstone of individualised neurocognitive assessment — is unavailable for the majority of patients presenting with TBI outside elite sport and military contexts. Without a baseline, clinicians must rely on normative data, which may not fully account for individual variability in cognitive ability. Practice effects — the tendency for scores to improve with repeated testing — further complicate serial assessment. GLIA's biomarker platform complements neurocognitive testing by providing an objective biological signal of neuronal injury that is independent of cognitive performance, effort, or baseline availability.
Common Neurocognitive Tools
The Current Landscape of Cognitive Assessment
ImPACT (Immediate Post-Concussion Assessment)
The most widely used computerised neurocognitive test in sport. Measures verbal and visual memory, processing speed, and reaction time. Requires a pre-injury baseline for optimal interpretation. Validated in collegiate and professional sport populations.
Cogstate
A brief computerised battery assessing processing speed, attention, learning, and working memory. Used in sport, military, and clinical research settings. Sensitive to acute concussion but susceptible to practice effects on serial testing.
ANAM (Automated Neuropsychological Assessment Metrics)
The US military standard computerised neurocognitive battery. Assesses processing speed, attention, memory, and executive function. Administered pre-deployment as a baseline and post-injury for comparison. Performance is affected by operational stress and fatigue.
Axon Sports (CogSport)
A brief computerised test using playing-card stimuli to assess processing speed, attention, and working memory. Designed for rapid sideline administration. Requires a pre-injury baseline and is not diagnostic in isolation.
MoCA (Montreal Cognitive Assessment)
A brief paper-based cognitive screening tool assessing visuospatial ability, naming, memory, attention, language, abstraction, and orientation. Widely used in clinical settings but not validated specifically for acute concussion assessment.
Trail Making Test
A neuropsychological test of processing speed, cognitive flexibility, and executive function. Part of comprehensive neuropsychological batteries. Sensitive to TBI-related cognitive impairment but requires trained administration and is not suitable for acute or field settings.
Cognitive Performance Is Not the Same as Brain Injury
Neurocognitive tests measure what the brain can do — not what has happened to it. GLIA's miRNA biomarker platform provides the biological evidence of neuronal injury that cognitive performance alone cannot establish.