DMDeepMindex

Science — the method

How the session becomes evidence.

Wearable EEG, PPG and respiration are read together, quality-checked before anything is scored, and compared with the practitioner’s own baseline. This is how the measures are built — and where their limits are.

Session profile

Three streams, checked before scoring.

Schematic

Wearable EEG

Attention

PPG

Regulation

Respiration

Breath

  • Segments below threshold are excluded before scoring.
  • Compared with the practitioner’s own baseline.
  • Reported with its uncertainty attached.
Illustrative schematic — not participant data.
Reads
Wearable EEG · PPG · respiration
Returns
Attention · regulation · recovery
Standard
Quality first · uncertainty stated

What the record can show

Three measures, read from one session.

Attention, regulation and recovery ask different questions of the same recording. Each is reported with its own uncertainty, and none is compressed into a single score for the whole sit.

  1. 01

    Attention is what the neural record can actually show

    Attention is the central claim of any practice, and the hardest thing to verify from the inside. It is easy to finish a session believing attention was steady when the record says otherwise.

    Wearable EEG gives the session a second opinion. DeepMindex reads the neural record for how attention behaved across the sit, rather than compressing it into one quality score for the whole session.

    Features drawn from the research base are treated as candidates and developed as candidates. Nothing is presented as a measure until it has survived validation.

    Read about the method
  2. 02

    Regulation appears in the pulse as well as the brain

    Physiological regulation describes how the autonomic system responds across a session: whether the body settles, and how quickly it recovers after effort or distraction.

    PPG-derived heart rate and pulse-rate variability carry that information. Working from pulse-rate variability rather than ECG matters here, because it is the signal a wearable can realistically record.

    Read alongside the EEG, regulation becomes part of the same session profile instead of a separate health metric kept in another app.

    Read about pulse-rate variability
  3. 03

    Recovery is a trend, not a single session

    One session tells you very little. Recovery is about whether regulation between sessions is improving, which only becomes visible across a series.

    DeepMindex therefore anchors every reading to the practitioner’s own baseline, built from their earlier sessions, and reports the trend rather than a single figure detached from it.

    That also means the platform deliberately avoids ranking one practitioner against another. A useful comparison is with your own history, not with the person on the next cushion.

    Read about individual baselines

How a reading earns trust

Anyone can draw a line. A measurement has to survive four checks.

Any sensor placed on a person will produce a line. The question worth asking of an assessment platform is whether that line can be trusted.

  1. 01

    Signal quality before scoring

    Every session is checked before it is scored, rather than after the fact.

    Segments that fail the quality threshold are excluded, not averaged into the result — so a reading that is nearly noise is not dressed up as a finding.

  2. 02

    A baseline that belongs to the practitioner

    Population norms describe populations. Applied to one person they can mislead, because an entirely ordinary session can sit well outside a range built from other people.

    Progress is measured against the practitioner’s own earlier sessions, and one practitioner is never ranked against another.

  3. 03

    The brain and the body, read together

    Neural and autonomic streams are modelled together, because attention and regulation move together.

    The output reads as one session profile rather than two disconnected dashboards.

  4. 04

    Uncertainty, stated plainly

    Every reading carries how confident the platform is in it.

    Where a trend is not yet meaningful, that is said rather than drawn as a line.

What still has to be proven

Some of what we measure is not yet established.

Candidate features drawn from existing recordings still have to hold up under wearable conditions, across experience levels and across sites.

That is the work of independent validation: reliability and generalisation, assessed rather than asserted.

We would rather state the limits of the method plainly than imply a maturity it has not reached.

Read about validation

The autonomic read-out

What pulse-rate variability shows — and what it does not.

PPG-derived pulse-rate variability is the autonomic signal a wearable can record continuously. It is informative, and it is easy to over-read.

R–R interval
Schematic

Pulse-rate variability as the autonomic read-out

The interval between heartbeats is never perfectly even. It tends to shorten slightly on inhalation and lengthen on exhalation, and the size of those fluctuations reflects the balance between sympathetic and parasympathetic influence on the heart.

That balance is one of the clearest available windows onto physiological regulation, which is why the platform reads it alongside the neural record rather than on its own.

Read more
movement artefactexcluded from scoring
Schematic

Why pulse rate, not ECG, for a wearable

Conventional variability measures are derived from ECG. PPG reads changes in blood volume at the skin instead, which is what a wearable can record continuously and unobtrusively — and pulse-rate variability is what PPG yields.

The trade-off is real: PPG is more exposed to movement artifact. That is precisely why signal quality is assessed first, and why poor segments are excluded rather than averaged into the result.

Read more
own baselines1s2s3s4s5s6
Schematic

What variability does and does not tell you

Variability measures describe autonomic activity. They are not a diagnosis, and they shift with sleep, posture, caffeine, illness and time of day.

DeepMindex therefore reads them against the practitioner’s own baseline, taken at comparable times, and reports the trend with its uncertainty rather than as a single ranked value.

Read more

Open questions

The questions the validation programme is working through

These are open research questions rather than completed studies. Each one will be published when it is through review.

In progress · Validation programme under way

01

Attention during practice

3 open questions
  1. How attention behaves across a single session, and whether that pattern is stable from session to session.
  2. Whether features drawn from existing recordings hold up when captured with wearable hardware instead of laboratory equipment.
  3. How the neural record differs by experience level, recorded under standardised protocols across cohorts.
02

Physiological regulation

3 open questions
  1. Whether PPG-derived pulse-rate variability tracks autonomic regulation closely enough to stand in for ECG-derived measures.
  2. How the neural and autonomic streams move together within a session, and whether either leads the other.
  3. How much of the variation between sessions is physiological rather than artefactual.
03

Recovery and baselines

3 open questions
  1. How many sessions are needed before an individual baseline is stable enough to measure against.
  2. Whether recovery between sessions is visible in the record at all, and over what timeframe.
  3. How baseline stability differs by practice frequency and experience level.
04

Signal quality and validation

3 open questions
  1. Which quality metrics predict whether a session will produce a usable result.
  2. How wearable recordings compare with laboratory-grade recordings of the same session.
  3. Independent validation of reliability and generalisation across cohorts and sites.
Portrait of Dr. Junling Gao.

Research foundation

The research behind the method

DeepMindex builds on long-standing research in EEG and meditation, and on an existing body of EEG and PPG recordings that includes three deep-jhana meditation recordings.

Those recordings capture states that are rarely measured in a laboratory at all. They guide candidate-feature development, subject to the applicable ownership, consent and data-use permissions.

Further data is collected using standardised protocols across experience levels, and independent validation assesses reliability and generalisation.

Dr. Junling Gao

Founder

Going further

Read the primary sources.

The method draws on published work in EEG, autonomic physiology and meditation research. These are the gateways we point people to, rather than rehosting the literature.

Collaboration

Work with us

For research access, collaboration on validation, or data-use enquiries, we welcome contact from academic groups and institutions.