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RESEARCH HUB

Built on research. Honest about its limits.

Each Nevuro task is informed by established research paradigms. This page shows what that research supports, what it does not, and what Nevuro still has to validate on its own.

One Nevuro session

  1. Reaction
  2. Attention
  3. Memory
  4. Nevuro Score

Reaction, Memory and Attention are short tasks within one integrated session, not separate tests. Together their measures form a session-level picture, summarised in the experimental Nevuro Score.

About the Nevuro Score: a product-level, experimental representation of one session. It is not a diagnostic score and has not been clinically validated.

01 / REACTION · TASK 1 OF 3

Reaction

Simple Reaction Time

A visual colour stimulus appears on the screen. The user responds by pressing any available physical button as quickly as possible.

Because the user does not have to select between multiple response buttons, the task minimizes response-selection demands. Reaction time is a composite behavioural measure involving sensory processing, central processing and motor execution — not the “pure speed” of a nerve impulse.

  1. 1Colour stimulus appears
  2. 2User presses any button
  3. 3Reaction time recorded

Constructs studied

  • Response speed
  • Response consistency

Measures

  • Reaction time
  • Median reaction time
  • Response-time variability
  • Missed / invalid responses

Andriuta et al., 2019 · Systematic review & meta-analysis

Simple reaction time is relevant to cognitive impairment research.

7 studies327 participants with MCI468 healthy controls

Mean simple reaction time was approximately 11% longer in the MCI group.

Relevance to Nevuro
SRT provides an established behavioural paradigm for measuring response speed.
Limitation
This does not establish a diagnostic threshold for Nevuro and does not mean that a slow Nevuro result indicates MCI or Alzheimer's disease.
PubMed DOI

Haynes, Bauermeister & Bunce, 2017 · Systematic review

Reaction-time variability may contain longitudinal information.

22 longitudinal studies

Greater intra-individual reaction-time variability at baseline was consistently associated with subsequent adverse outcomes, including cognitive decline, cognitive impairment and dementia.

Relevance to Nevuro
Nevuro can preserve trial-level reaction-time data and investigate response consistency over repeated sessions.
Limitation
Reaction-time variability is not specific to neurodegenerative disease and does not make Nevuro a dementia detector.
PubMed DOI

Dykier et al., 2012 · Systematic review & meta-analysis

Reaction-time variability also changes with normal ageing.

Older adults showed greater RT variability than younger and middle-aged adults; age effects were larger in choice RT than in simple RT.

Relevance to Nevuro
A Reaction session can reasonably retain trial-level RT data rather than only one average score.
Limitation
RT variability is not specific to neurodegenerative disease and changes with normal ageing as well.
PubMed DOI
02 / ATTENTION · TASK 2 OF 3

Attention

Choice Reaction Time with visual distractor interference

The user must identify the relevant colour and press the corresponding physical button while competing visual stimuli act as distractors.

The task introduces attentional and interference-control demands. It is not labelled a Flanker Task: Flanker results depend strongly on task design, stimulus type, spatial arrangement and scoring method, and Nevuro has not implemented or validated that exact paradigm.

  1. 1Target + distractors
  2. 2Identify target
  3. 3Select corresponding button
  4. 4Ignore distractors

Constructs studied

  • Selective attention
  • Response selection
  • Interference control

Measures

  • Reaction time
  • Accuracy
  • Incorrect responses
  • Missed targets
  • Response-time variability
  • Distractor interference effect — only if the protocol contains comparable conditions

Nebes et al.

Choice reaction time has been used to study focused attention.

The study described simple RT as a psychomotor-speed task and choice RT as a focused-attention task, and reported significant CRT differences in Alzheimer's disease compared with normal elderly controls, and slowed RT in MCI.

Relevance to Nevuro
Choice reaction time provides a scientific framework for studying performance that requires response selection.
Limitation
The study does not validate the exact Nevuro Attention task.
PubMed

Selective-attention ageing literature

Interference tasks examine performance in the presence of irrelevant information.

Research on selective attention in ageing examines how people process relevant information in the presence of irrelevant information. Age-related changes in selective attention and distraction are described, although effects depend strongly on modality and task design.

Relevance to Nevuro
Introducing visual distractors is scientifically defensible as a way of increasing attentional competition.
Limitation
The presence of distractors does not make the task a standardized Flanker Task and does not establish that Nevuro measures a clinically validated inhibitory-control construct.
PubMed Distractibility review Guay et al., 2026
03 / MEMORY · TASK 3 OF 3

Memory

Spatial Span / visuospatial working memory

The user observes a sequence of colour stimuli and reproduces the sequence using physical buttons.

Nevuro Memory uses a sequential visual-spatial memory paradigm related to the Spatial Span / Corsi Block-Tapping tradition. It is not the Corsi test itself — and computerized or button-based implementations require their own validation rather than being assumed equivalent.

  1. 1Sequence appears
  2. 2User observes
  3. 3Sequence disappears
  4. 4User reproduces sequence
  5. 5Accuracy recorded

Constructs studied

  • Visuospatial working memory
  • Sequential span

Measures

  • Maximum sequence length
  • Correctly reproduced sequences
  • Recall accuracy
  • Errors
  • Response time, if implemented

Berch et al., 1998 · Fischer, 2001

Spatial Span is an established visuospatial working-memory paradigm.

The Corsi Block-Tapping Task has been extensively used in clinical and experimental research and is described as involving spatial memory span and visuospatial working-memory processes.

Relevance to Nevuro
Spatial Span provides an established scientific framework for studying visuospatial working-memory performance.
Limitation
Nevuro Memory is not automatically equivalent to a standardized Corsi test.
PubMed · Berch PubMed · Fischer

Clinical geriatric population study

Spatial Span performance differs across cognitive-impairment groups.

538 adultsAged 65–89

Greater cognitive impairment was associated with lower Spatial Span Total Scores. Spatial Span Backward was more sensitive to severity than Forward.

Relevance to Nevuro
Spatial Span is an established cognitive paradigm relevant to visuospatial working memory.
Limitation
These findings concern established neuropsychological measures and do not establish equivalent validity for Nevuro Memory.
PubMed DOI

Sabahi et al., 2022 · Systematic review & meta-analysis

Working-memory measures show differences in MCI.

14 studies in review7 in meta-analysis

Significant differences between MCI and healthy controls were reported for CANTAB spatial working memory and spatial span.

Relevance to Nevuro
Working-memory and spatial-span performance are scientifically relevant domains for studying cognitive impairment.
Limitation
The CANTAB findings cannot be transferred directly to Nevuro's colour-sequence task.
PubMed DOI
04 / REPEATED TESTING

Change over time is harder than it looks.

White et al., 2019

Practice effects appear early in repeated computerized testing.

30 healthy older menAged 65–716 testing sessions

Practice effects were observed on multiple RT, selective-attention and working-memory measures, especially between the first two testing points. Computerized Corsi metrics tended to show poor reliability.

Relevance to Nevuro
Nevuro cannot assume a memory mechanic is reliable because it resembles an established task; longer familiarization may be needed.
Limitation
Results concern a different battery and population, not Nevuro.
PubMed DOI

Rijnen et al., 2018

Reliability varies — and practice effects persist at 3 months.

158 healthy adultsRetested at 3 & 12 months

Reliability ranged from low to high depending on the measure, with significant practice effects at 3 months for cognitive flexibility, processing speed and reaction time.

Relevance to Nevuro
Imperfect reliability and practice effects must be accounted for when evaluating Nevuro performance over time.
Limitation
A change between two Nevuro sessions cannot currently be assumed to represent genuine cognitive change.
PubMed

Factors that can affect any session

SleepFatigueStressIllnessMedicationSensory functionMotor functionMotivationPractice effectsTesting environment
05 / EVIDENCE MATRIX

Claim by claim.

ClaimEvidenceRelevanceLimitationSources
Simple reaction time is an established behavioural measurement paradigm.Meta-analysis of 7 studies; slower SRT in MCI.Reaction measures response latency and variability.Not a validated clinical SRT instrument.
PubMed
Reaction-time variability has longitudinal associations with cognitive outcomes.Systematic review of 22 longitudinal studies.Supports retaining trial-level RT data.Not specific to neurodegenerative disease.
PubMed
Choice reaction time can be used to study focused attention.CRT compared across AD, MCI and normal elderly.Framework for the Attention task.Does not validate the Nevuro Attention task.
PubMed
Distractor paradigms study attentional competition, but effects depend on task design.Selective-attention ageing literature; Flanker meta-analysis.Distractors raise attentional demands.Not a Flanker Task; no validated inhibition measure.
PubMed PubMed
Spatial Span is an established visuospatial working-memory paradigm.Corsi / Spatial Span literature.Framework for the Memory task.Not equivalent to standardized Corsi.
PubMed PubMed
Spatial Span performance differs across cognitive-impairment groups.538 adults aged 65–89; CANTAB meta-analysis.Spatial memory is a relevant domain.Findings cannot be transferred to Nevuro.
PubMed PubMed
Repeated computerized cognitive testing is affected by practice effects.6-session and 3/12-month retest studies.Defines what Nevuro must control for.Nevuro-specific estimates still needed.
PubMed PubMed
06 / STILL TO VALIDATE

What Nevuro must prove itself.

Research supports the underlying concepts. It does not yet validate the Nevuro implementation.

  1. 01

    Construct validity

    Does each task measure the intended construct?

  2. 02

    Convergent validity

    How do Nevuro scores relate to established cognitive tests?

  3. 03

    Test-retest reliability

    How stable are scores when cognition has not meaningfully changed?

  4. 04

    Practice effects

    How much change comes from familiarity?

  5. 05

    Sensitivity to change

    Can Nevuro detect meaningful within-person change?

  6. 06

    Specificity

    Can cognitive change be distinguished from fatigue, illness and other factors?

  7. 07

    Normative data

    How do results vary with age, education, language and other characteristics?

  8. 08

    Longitudinal validity

    Do Nevuro trajectories correspond to meaningful cognitive outcomes?

07 / BOUNDARIES

What Nevuro does not claim.

  • Does not diagnose Alzheimer's disease
  • Does not diagnose dementia
  • Does not predict when dementia will occur
  • Does not replace clinical assessment
  • Does not prevent dementia
  • Does not treat cognitive disease
  • Does not interpret one abnormal session as disease

Concerns about memory or thinking need a clinical evaluation, which can include:

Medical historyCognitive assessmentFunctional assessmentInformant informationPhysical examinationLaboratory investigationInvestigation of reversible causesSpecialist assessmentImaging or biomarkers where appropriate
08 / RESEARCH LIBRARY

Every study we cite.

15 of 15 studies

Andriuta et al. · 2019 · Systematic review / meta-analysis

Is Reaction Time Slowing an Early Sign of Alzheimer's Disease? A Meta-Analysis

7 studies · 327 MCI + 468 controls

Mean SRT was approximately 11% longer in MCI.

Relevance: Supports the scientific relevance of SRT as a measurable performance variable.

Does not show: Nevuro can diagnose MCI or dementia.

PubMed DOI

Dykier et al. · 2012 · Systematic review / meta-analysis

Age differences in intra-individual reaction-time variability

Simple and choice RT studies

Older adults showed greater RT variability; age effects were larger in choice than simple RT.

Relevance: Supports retaining trial-level RT data, not only an average.

Does not show: That RT variability is specific to neurodegenerative disease.

PubMed DOI

Haynes, Bauermeister & Bunce · 2017 · Systematic review

Longitudinal studies of reaction-time intra-individual variability

22 longitudinal studies

Greater baseline IIV was consistently associated with adverse outcomes including cognitive decline/impairment and dementia.

Relevance: Repeated Reaction trials may provide information about response consistency over time.

Does not show: That Nevuro's SRT task can predict dementia.

PubMed DOI

Nebes et al. · — · Comparative study

Focused attention and choice reaction time in MCI and Alzheimer's disease

AD, MCI and normal elderly controls

Significant CRT differences in AD vs. normal elderly controls; slowed RT in MCI.

Relevance: CRT is an established way to study response selection and focused attention.

Does not show: The validity of the exact Nevuro Attention task.

PubMed

Guay et al. · 2026 · Systematic review / meta-analysis

Flanker task and age-related inhibitory control

Flanker-task studies

Flanker results depend strongly on task design, stimulus type, spatial arrangement and inhibition-cost calculation.

Relevance: Explains why Nevuro Attention is not labelled a Flanker Task.

Does not show: That Nevuro measures inhibitory control.

PubMed DOI

Zanto & Gazzaley (related literature) · — · Review

Selective attention in ageing

Selective-attention ageing research

Age-related changes in selective attention and distraction, with effects depending on modality and task design.

Relevance: Distractors are a defensible way to increase attentional competition.

Does not show: A clinically validated inhibitory-control construct in Nevuro.

PubMed

Hasher & Zacks (related review) · — · Review

Cognitive ageing and distractibility

Cognitive ageing research

Increased distractibility can be consequential when irrelevant information interferes with the current task.

Relevance: Context for including visual distractors.

Does not show: That the Nevuro task is validated.

PubMed

Berch et al. · 1998 · Paradigm literature

Corsi Block-Tapping Task

—

Corsi is widely used and involves spatial memory span and visuospatial working memory.

Relevance: Grounds Memory in an established paradigm.

Does not show: Equivalence of Nevuro Memory to Corsi.

PubMed

Fischer · 2001 · Paradigm literature

Corsi and spatial working memory

—

Describes Corsi in terms of spatial memory span and visuospatial working-memory processes.

Relevance: Grounds Memory in an established paradigm.

Does not show: Equivalence of Nevuro Memory to Corsi.

PubMed

Claessen et al. · 2014 · Validation study

Computerized Corsi Block-Tapping

—

Computerization can alter underlying cognitive concepts and requires its own validation.

Relevance: Nevuro's button/screen implementation needs its own validation.

Does not show: Anything about Nevuro's psychometric properties.

PubMed DOI

— · — · Comparative study

Spatial Span in a clinical geriatric population

538 adults aged 65–89

Higher impairment associated with lower Spatial Span Total Scores; Backward more sensitive to severity than Forward.

Relevance: Spatial Span is relevant to visuospatial working memory.

Does not show: Equivalent validity for Nevuro Memory.

PubMed DOI

Sabahi et al. · 2022 · Systematic review / meta-analysis

CANTAB working memory in MCI

14 studies (7 in meta-analysis)

Significant MCI vs. control differences in spatial working memory and spatial span.

Relevance: Working memory is a relevant domain for studying cognitive impairment.

Does not show: That CANTAB findings transfer to Nevuro's colour-sequence task.

PubMed DOI

White et al. · 2019 · Repeated-measures study

Repeated computerized testing in older adults

30 healthy men aged 65–71 · 6 sessions

Practice effects on RT, selective-attention and working-memory measures, especially early; computerized Corsi showed poor reliability.

Relevance: Nevuro must estimate its own practice effects and reliability.

Does not show: Anything about Nevuro's reliability.

PubMed DOI

Rijnen et al. · 2018 · Test-retest study

Test-retest reliability and practice effects

158 healthy Dutch adults · 3 & 12 months

Low-to-high reliability by measure; practice effects at 3 months for flexibility, processing speed and RT.

Relevance: Defines the need for reliable-change thresholds.

Does not show: That Nevuro session changes reflect cognitive change.

PubMed

Rijnen et al. · 2020 · Normative study

Normative data and sociodemographic variables

Dutch participants

Performance differences associated with education and sex, in addition to age.

Relevance: Nevuro should distinguish personal baseline from population norms.

Does not show: That a personal baseline makes results clinically interpretable.

PubMed
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