In most areas of medicine, clinical progress depends on measurement. Biomarkers, imaging, physiological data are the tools through which treatment is calibrated, response is tracked, and outcomes are understood.
Brain health has largely operated without this. Progress has typically been inferred from how patients describe feeling, despite the fact that in almost any other field of medicine, this alone would be considered insufficient.
This is the gap that precision brain health is beginning to close.
What Do We Mean by Brain Health?
Brain health has many dimensions. It encompasses how well the brain regulates mood and stress responses, how efficiently it processes and retains information, how effectively it recovers through sleep, through rest, and through treatment.
When these dimensions are functioning well, the results are clear: emotional resilience, mental clarity, stable energy, restorative sleep. When they are not, the effects are equally recognisable: difficulty regulating mood, cognitive fatigue, disrupted sleep, a reduced capacity to adapt to stress.
Much like physical health, brain health is not fixed. It can be nurtured, trained and improved. The mechanism behind this is neuroplasticity: the brain's capacity to reorganise, adapt and form new connections.
Why Has Brain Health Been So Difficult to Measure?
The brain does not offer up its signals easily. Unlike cardiovascular health, which can be assessed through blood pressure, lipid panels and imaging, or metabolic health, which has well-established biomarker frameworks, brain health has historically lacked equivalent objective measures.
Clinical assessment has relied heavily on symptom questionnaires and patient self-report. These tools have value and are widely used. They capture how someone feels about their experience. They do not capture what is biologically changing.
This has had real consequences. It has made it harder to identify who is likely to respond to treatment, harder to detect progress that the patient may not yet consciously register, and harder to refine protocols in response to what the data is showing. The field has been navigating, in large part, without instruments.
What Can Be Measured?
There are now several validated domains through which brain health can be objectively monitored through accessible, repeatable measures that together build a meaningful picture.
Heart rate variability is one of these. Specifically RMSSD, a measure of beat-to-beat variation in the heart, reflects the balance of the autonomic nervous system and parasympathetic activity in particular. The autonomic nervous system is deeply connected to brain regulation. Shifts in HRV across a treatment course are a meaningful signal of neurological change.
Sleep architecture is another. This encompasses the quality and structure of sleep itself, the proportion of deep sleep and REM, and how these shift over time. Sleep is both a predictor and an outcome of neural recovery. Disrupted architecture limits the brain's capacity to consolidate change. Improvement in architecture is a sign that something real is happening.
Cognitive performance, assessed through validated testing batteries, provides a direct functional measure of response inhibition, attention, visuospatial processing, verbal short-term memory, working memory and episodic memory. These are capabilities that change with treatment, and that change can be tracked.
Metabolic and inflammatory markers, including glycaemic control, lipid profile and markers of systemic inflammation, have an established relationship with neuroplasticity. Poor metabolic health constrains the brain's capacity to adapt and recover. These are state factors: baseline conditions that either support or limit what treatment can achieve.
Finally, neuromuscular function. Perhaps the least intuitive measure, but well-validated as a proxy marker of parasympathetic nervous system activity and biological age. Across a treatment course, improvements in grip strength, specifically in the rate of force development, reflect autonomic recalibration. Increased neuromuscular function indicates that the brain is in better communication with the body.
No single marker tells the full story. Together, tracked longitudinally, they begin to build one.
How Does Measurement Change Treatment?
Objective monitoring changes what treatment can be. Rather than relying solely on how someone reports feeling week to week, it becomes possible to track real biological and functional change as it unfolds, and to use that data to tailor and refine the treatment programme accordingly.
Where baseline measures suggest factors that might limit response, these can be identified and addressed before or during treatment. Where the data shows meaningful change across domains, that progress becomes visible and concrete, to the clinician and to the patient.
This is what precision brain health means in practice: treatment that is continuously informed by what is actually happening.
Introducing NayaScore™
NayaScore™ is Naya Health's proprietary brain health monitoring platform, the first longitudinal, multi-domain measure of brain health we are aware of. It brings together the domains described above, autonomic regulation, sleep architecture, cognitive performance, metabolic health and neuromuscular function, into a single composite score that evolves across the course of a treatment programme.
It is designed to do two things: make brain health visible, and make treatment smarter. For patients, it means an objective, evolving picture of what is changing and why. For the field, it represents a step toward the standard of measurement that brain health has always warranted.
Brain health has not been unmeasurable. It has been unmeasured. That distinction is what NayaScore™ is built on.