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Not yet recruitingNCT07903688SPANDHAUpdated Nov 10, 2026

Meditation and Yogic Breathing-driven Modulation of Neurofluid Coupling and Brain Clearance

An interventional study of Nadi Shuddhi and Shoonya Meditation in Healthy, sponsored by Beth Israel Deaconess Medical Center. Not yet recruiting at 1 site in United States. Open to participants aged 25 Years to 60 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-11-10.

Sponsored by Beth Israel Deaconess Medical Center · Not applicable, Interventional, and Other

Updated Oct 29, 2026Newly registeredGo to Updates ↓
Phase
Not applicable
Study type
Interventional
Enrollment
120
Allocation
Non-randomized
Ages
25 Years to 60 Years
Sex
All
01

Study summary

This study will examine whether meditation and yogic breathing can alter brain fluid movement and waste clearance in healthy adults. It will also evaluate the GLYMPHOMETER, a new external forehead-worn device designed to objectively measure changes in brain fluid movement and exchange during meditation.

Read the detailed description

The glymphatic system is a brain waste-clearance pathway that facilitates the movement of cerebrospinal fluid (CSF) and interstitial fluid and is thought to play an important role in maintaining brain homeostasis. Emerging evidence suggests that respiration, autonomic activity, and changes in cerebral blood flow may influence CSF dynamics and related neurofluid processes. However, the effects of voluntary breathing practices and meditation on these physiological mechanisms in humans remain incompletely understood.

The SPANDHA study will investigate whether structured yogic breathing (Pranayama; specifically Nadi Shuddhi) and/or meditation (Shoonya meditation) are associated with changes in neurofluid dynamics and related physiological measures. The study will use the GLYMPHOMETER, a forehead-mounted multimodal device designed to measure physiological signals associated with neurofluid coupling during naturalistic meditation and breathing practices. The system incorporates multi-wavelength electroencephalography (EEG) and near-infrared spectroscopy (NIRS) to characterize changes in cerebral electrical activity, cerebral hemodynamics, and neurofluid-related dynamics while participants engage in the interventions.

The study will enroll approximately 100 participants, including 50 novice and 50 experienced practitioners. Using a 2-sequence crossover, participants will complete two study visits involving meditation and yogic breathing conditions. The study will evaluate changes in measures of neurofluid dynamics, cerebral compliance, autonomic regulation including heart-rate variability (HRV), and EEG-derived brain states associated with the interventions. Participants will be stratified by experience level (novice/advance) and randomized within each stratum to one of the two intervention sequences.

A subset of participants will undergo additional validation assessments using phase-contrast magnetic resonance imaging (MRI) and blood-based biomarkers. These assessments will be used to examine the relationship between measurements obtained with the GLYMPHOMETER and established measures of CSF and cerebrovascular physiology.

The primary objective of the study is to characterize the acute physiological effects of meditation and yogic breathing on neurofluid dynamics and related brain and autonomic measures. The findings may provide preliminary evidence regarding the feasibility of using voluntary breathing and meditation practices to modulate physiological processes associated with glymphatic function and may inform future studies of non-pharmacological approaches to brain health.

02

Conditions studied

  • Healthy

Keywords

  • Shoonya
  • Glymphometer
  • neurofluidics
03

In context

Lead sponsor

Beth Israel Deaconess Medical Center is the lead sponsor of 568 studies on the registry; 80 are open to participants now.

Of its 76 completed or terminated interventional studies of FDA-regulated products, 62 (82%) have results posted.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
25 Years to 60 Years
Sexes eligible
All
Accepts healthy volunteers
Yes

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • Healthy adults, 25-60 years old.
  • Novice or Advanced as defined above.
  • Fluent in English.
  • Able to travel to BIDMC site for two days approximately 3-7 days apart.

Exclusion criteria

Exclusion Criteria:

  • History of neurological and/or neurodegenerative disorders (e.g., epilepsy, stroke, mild cognitive impairment, dementia)
  • History of cardiovascular and respiratory illnesses
  • History of major psychiatric disorders (e.g., schizophrenia, bipolar disorder)
  • Currently diagnosed mental health issues (e.g., anxiety, depression)
  • Current use of psychoactive medications, including medications prescribed for anxiety, depression, or other psychiatric conditions, or current use of stimulants or other medications that may substantially affect central nervous system function or study outcomes.
  • Skin ailments, abrasions or contusions, particularly located on the forehead and face
05

Study design

Phase
Not applicable
Primary purpose
Other
Allocation
Non-randomized
Intervention model
Crossover assignment
Masking
None (open label)
Enrollment
120 participants (estimated)

Study arms

  • Active comparator
    Novice Meditators

    Less than 1 year of consistent meditation practice.

    Behavioral: Nadi Shuddhi · Behavioral: Shoonya Meditation

  • Active comparator
    Advanced Meditators

    More than 5 years or a minimum of 2500 hours of consistent meditation practice

    Behavioral: Nadi Shuddhi · Behavioral: Shoonya Meditation

Interventions

  • BehavioralNadi Shuddhi

    Nadi Shuddhi is a structured yogic breathing practice involving slow, alternating respiration through the left and right nostrils in a prescribed sequence.

  • BehavioralShoonya Meditation

    Shoonya meditation is a structured contemplative practice characterized by conscious non-doing, in which participants maintain a relaxed, alert state while minimizing deliberate attentional selection, cognitive elaboration, and engagement with internal or external stimuli.

06

What researchers measure

Primary outcomes

  1. Acquisition of physiological data using the GLYMPHOMETER during meditation and yogic breathing sessions.

    Participants meeting threshold for analyzable device recordings.

    Time frame: At each study visit while the meditation is being practiced. Expected acquisition window: 20 minutes; Total number of visits: 2

Secondary outcomes

  1. Neurofluid-related physiological measures during Shoonya meditation and Nadi Shuddhi breathing.

    Changes in GLYMPHOMETER-derived measures of neurofluid coupling, during Shoonya meditation and Nadi Shuddhi breathing. (Measurement device: Glymphometer; Measure: Neurofluid coupling aka Fluid dynamics in brain)

    Time frame: At each study visit while the meditation is being practiced. Expected acquisition window: 20 minutes; Total number of visits: 2

  2. Autonomic regulation during Shoonya meditation and Nadi Shuddhi breathing.

    Changes in heart-rate variability (HRV) during Shoonya meditation and Nadi Shuddhi breathing.

    Time frame: At each study visit while the meditation is being practiced. Expected acquisition window: 20 minutes; Total number of visits: 2

  3. Very-low-frequency physiological signal characteristics

    Changes in predefined very-low-frequency (0.001-0.1 Hz) signal characteristics derived from GLYMPHOMETER medical™ recordings and their relationship to neurofluid-related measures.

    Time frame: At each study visit while the meditation is being practiced. Expected acquisition window: 20 minutes; Total number of visits: 2

Other outcomes

  1. Differences in neurophysiological responses according to meditation experience.

    Comparison of changes in GLYMPHOMETER-derived measures of neurofluid coupling between novice and advanced meditators.

    Time frame: From date of enrollment until end of both study visits; assessed up to 4 weeks from enrollment.

  2. Mindful Attention Awareness Scale

    We assess for change in Mindfulness levels by using a validated scale for this purpose namely, Mindfulness Attention Awareness Scale (MAAS). The scale measures the individuals' ability for receptive awareness and attention to present. This aids in evaluating any change on the individual's awareness levels after the Inner engineering intervention. We compute the MAAS scores for each participant which is a mean score for 15 item questionnaires and compare the pre \& post intervention results to look for change. Participants are asked to rate on a scale of 1 (Almost Always) to 6 (Almost Never) to assess the frequency of occurrence of each experience. Mean is then computed using items from each of the 15 questions to create a MAAS score, ranging from 0 to 6. Higher MAAS scores indicate better mindfulness state.

    Time frame: Once at Baseline. Estimated acquisition window: 5-8 minutes

  3. Meditation Depth Questionnaires

    This 30-item measure assesses the subjective depth of meditation across progressively deeper experiential states. Items are typically rated on a 5-point Likert scale and are grouped into five empirically derived domains: hindrances, relaxation, personal-self/concentration, essential/transpersonal qualities, and transpersonal-self/non-duality. Together, these domains capture experiences ranging from obstacles and relaxation during meditation to focused concentration, transpersonal qualities, and experiences of diminished self-boundaries or non-dual awareness.

    Time frame: At each study visit after the meditation practice is completed. Expected acquisition window: 10-15 minutes; Total number of visits: 2

  4. Correlation between GLYMPHOMETER-derived neurofluid metrics and MRI-based neurofluid dynamics (Validation of Portable Device).

    This outcome evaluates the concurrent validity of the portable device against the gold standard. The statistical method will be a correlation analysis (Pearson or Spearman, as appropriate based on data distribution). * Measurement 1 (Variable A): Neurofluid coupling oscillations measured via the GLYMPHOMETER medical™ device (measured as relative changes in HbO, HbR, HbT, and CSF/H2O proportional signal including interhemispheric correlation coefficient across these neurofluid compartments while gating each of them to very low frequency, respiratory and cardiac frequency bands). * Measurement 2 (Variable B): Global neurofluid dynamics and CSF flow measured via 3T MRI using fast fMRI and phase-contrast sequences (measured as BOLD-CSF coupling magnitude and CSF stroke volume in mL). * Assessment: The study will assess the correlation between the magnitude of oscillatory coupling in Measurement 1 with the absolute flow dynamics in Measurement 2 during the designated validation windows.

    Time frame: From date of enrollment until end of both study visits; assessed up to 4 weeks from enrollment.

  5. Correlation between GLYMPHOMETER-derived neurofluid metrics and plasma brain-derived biomarkers.

    This outcome evaluates the relationship between neurofluid dynamics and blood-based markers of brain clearance. The statistical method will be a correlation analysis (Pearson or Spearman). * Measurement 1 (Variable A): Neurofluid coupling oscillations measured via the GLYMPHOMETER medical™ device (measured as relative changes in HbO, HbR, HbT, and CSF/H2O proportional signal including interhemispheric correlation coefficient across these neurofluidic compartments while gating each of them to very low frequency, respiratory and cardiac frequency bands). * Measurement 2 (Variable B): Plasma concentrations of brain-derived proteins/peptides (Aβ40, Aβ42, total/phosphorylated tau, NF-L, GFAP) measured via ultra-sensitive Simoa immunoassay (measured in pg/mL). * Assessment: The study will assess the correlation between acute GLYMPHOMETER-derived neurofluid changes and plasma biomarker concentrations before and after intervention.

    Time frame: From date of enrollment until end of both study visits; assessed up to 4 weeks from enrollment.

  6. Qualitative assessment of meditation and breathing experiences.

    Qualitative characterization of participant experiences using one-on-one micro-phenomenological interviews.

    Time frame: At each study visit after the meditation practice is completed. Expected acquisition window: 30 minutes; Total number of visits: 2

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Study locations

1 site
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References and documents

Individual participant data

Plan to share: Undecided

No publications or documents are linked to this record.

09

Updates

2 registry updates since Sep 25, 2026
Secondary outcomes
1 time frame changed
What changed in the outcomes
  • Time frameother outcomeMindful Attention Awareness ScaleOnce at Baseline. Estimated acquisition window: 5-8 mins → Once at Baseline. Estimated acquisition window: 5-8 minutes
Nov 10, 2026
Registered
First appeared on the registry
Oct 29, 2026
Show all 2 updates
  1. Nov 10, 2026
    Secondary outcomes 1 time frame changed
    What changed in the outcomes
    • Time frameother outcomeMindful Attention Awareness ScaleOnce at Baseline. Estimated acquisition window: 5-8 mins → Once at Baseline. Estimated acquisition window: 5-8 minutes
  2. Oct 29, 2026
    First appeared on the registry

From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗

10

Registry details

Key details

Study ID
NCT07903688
Responsible party
Balachundhar Subramaniam (Staff Physician, Beth Israel Deaconess Medical Center) — Principal investigator
First posted
Oct 29, 2026
Start date
Nov 16, 2026 (estimated)
Primary completion
Nov 30, 2027 (estimated)
Completion
Apr 30, 2028 (estimated)
Last update
Nov 10, 2026

Study contacts

Balachundhar Subramaniam, MD MPH
Contact
bsubrama@bidmc.harvard.edu
(781) 472-0572

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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