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Intensive breathwork reduces brain blood flow and alters neural communication (opens in a new tab)

news-medical.net · 2026-10-11

Short answerEvidenceSource

Short answer

Mixed

Mixed.

One key claim is not backed by the study. One other point was not covered by the paper.

  • 3 supported
  • 3 overstated
  • 1 not supported
  • 1 not covered

Checked against the study summary. The full text wasn't available, so some details couldn't be settled either way.

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Follow the evidence trail
1
2

NewsLink checks it

Mixed

Four claims go beyond the study. Three overstate it and one isn't supported at all. One claim the study doesn't address.

  • 3 supported
  • 3 overstated
  • 1 not supported
  • 1 not covered
Open claim evidence
3
Then inspect each claim

Evidence layer

Claim by claim

Each claim gets a verdict. Expand it to see the evidence directly below.

8 claims in this story

Showing all 8 claimsChoose a verdict to focus the list.

Claim 1 of 8Not supportedBrain imaging showed that global grey-matter cerebral blood flow fell by around 45% during the session, on average from 16.24 to 9.81 ml/100g/min.View evidenceHide evidence

As statedaround 45%; from 16.24 to 9.81 ml/100g/min

Why this verdict

The direction and approximate percent reduction are supported, but the absolute values are not. The profile reports a 45.5% reduction from 29.81 ± 7.58 to 16.24 ± 4.35 mL/100 g/min, not from 16.24 to 9.81 mL/100 g/min. Because the claim gives incorrect numerical endpoints for a central result, it is unsupported as stated.

1

Study evidence

Acute high ventilation breathwork produced a large reduction in global grey-matter cerebral blood flow measured by ASL during the interval of maximal subjective effects.45.5% reduction; 29.81 ± 7.58 vs. 16.24 ± 4.35 mL/100 g/min; t(29) = -10.69, p < 0.001

“Thirty experienced HVB practitioners (mean age 44.97 ± 11.80 years) underwent perfusion and resting-state fMRI to assess acute cerebrovascular and post-acute network changes.”
Claim 2 of 8OverstatedIntensive breathing exercises can reduce blood flow to the brain by up to 45% and alter communication between brain networks, according to a new brain-imaging study.View evidenceHide evidence

As statedup to 45%

Why this verdict

The 45.5% acute reduction in global grey-matter CBF during high-ventilation breathwork is supported, but the headline-level claim that breathwork 'alter[s] communication between brain networks' is stronger than the abstract evidence. The paper profile says DMN functional connectivity did not change significantly at the group level, and the DMN–ASC relationship was exploratory and preprocessing-dependent. The headline therefore outruns the more qualified body framing.

1

Study evidence

Acute high ventilation breathwork produced a large reduction in global grey-matter cerebral blood flow measured by ASL during the interval of maximal subjective effects.45.5% reduction; 29.81 ± 7.58 vs. 16.24 ± 4.35 mL/100 g/min; t(29) = -10.69, p < 0.001

“Thirty experienced HVB practitioners (mean age 44.97 ± 11.80 years) underwent perfusion and resting-state fMRI to assess acute cerebrovascular and post-acute network changes.”
2

Study evidence

No significant group-level change in default mode network (DMN) functional connectivity from pre to post HVB in 30 practitioners.

“Thirty experienced HVB practitioners ... underwent perfusion and resting-state fMRI to assess acute cerebrovascular and post-acute network changes.”
Claim 3 of 8OverstatedThe researchers say changes in brain communication, rather than reduced blood flow alone, appear to be key to the altered state.View evidenceHide evidence

Why this verdict

The paper profile supports the idea that CBF reduction alone did not explain subjective altered-state intensity, because CBF reductions were not associated with 5D-ASC ratings. However, saying brain-communication changes 'appear to be key' overstates the abstract evidence: there was no robust group-level DMN FC change, and the DMN-FC/5D-ASC association was exploratory and significant only with global signal regression.

1

Study evidence

No significant group-level change in default mode network (DMN) functional connectivity from pre to post HVB in 30 practitioners.

“Thirty experienced HVB practitioners ... underwent perfusion and resting-state fMRI to assess acute cerebrovascular and post-acute network changes.”
2

Study evidence

Greater decreases in DMN functional connectivity (pre → post) predicted higher 5D-ASC ratings when analyses used global signal regression, but the association was not significant without global signal regression.β = -4.88 (p < 0.05 with GSR; p = 0.75 without GSR)

“In further exploratory analyses, greater decreases in DMN FC (pre - post breathwork) predicted higher 5D-ASC rating (β = -4.88, p < 0.05) in analyses using global signal regression, though this association was not significant without global signal regression (p = 0.75).”
Claim 4 of 8OverstatedThose who reported stronger altered states also showed greater changes in the brain's default mode network, which is involved in self-reflection and self-related thinking.View evidenceHide evidence

Why this verdict

The profile reports an exploratory association in which greater decreases in DMN FC predicted higher 5D-ASC ratings only when global signal regression was used; the association was not significant without GSR, and there was no significant group-level DMN FC change. The claim omits these robustness caveats and presents the relationship too definitively. The profile also does not substantiate the explanatory description of the DMN as involved in self-reflection at abstract depth.

1

Study evidence

No significant group-level change in default mode network (DMN) functional connectivity from pre to post HVB in 30 practitioners.

“Thirty experienced HVB practitioners ... underwent perfusion and resting-state fMRI to assess acute cerebrovascular and post-acute network changes.”
2

Study evidence

Acute psychotropic effects were rated during the HVB session using an online Likert scale; altered-state intensity was assessed immediately after breathwork with the 5D-ASC.

“Acute psychotropic effects were rated using an online Likert scale, ASC intensity was assessed immediately after breathwork with the 5-Dimensional Altered States of Consciousness (5D-ASC) scale.”
Claim 5 of 8Not coveredParticipants reported experiences resembling some effects of psychedelic drugs, including altered perception, vivid mental imagery, a sense of unity and changes in self-experience.View evidenceHide evidence

Why this verdict

The abstract-level profile supports that acute psychotropic effects and altered-state intensity were measured with self-report instruments, including the 5D-ASC. It does not provide the specific reported phenomenology listed here—altered perception, vivid imagery, unity, or changes in self-experience—nor does it substantiate the detailed comparison to psychedelic drug effects at this depth.

1

Study evidence

Acute psychotropic effects were rated during the HVB session using an online Likert scale; altered-state intensity was assessed immediately after breathwork with the 5D-ASC.

“Acute psychotropic effects were rated using an online Likert scale, ASC intensity was assessed immediately after breathwork with the 5-Dimensional Altered States of Consciousness (5D-ASC) scale.”
Claim 6 of 8SupportedThe study involved 30 healthy, experienced breathwork practitioners who performed high-ventilation breathwork during MRI scanning.View evidenceHide evidence

As stated30 participants

Why this verdict

The abstract profile states that 30 experienced HVB practitioners underwent perfusion and resting-state fMRI, with CBF measured during baseline and maximal subjective effects. The profile does not separately document the word 'healthy' at abstract depth, but the central sample size, practitioner status, HVB intervention, and MRI-scanning context are supported.

1

Study evidence

Acute high ventilation breathwork produced a large reduction in global grey-matter cerebral blood flow measured by ASL during the interval of maximal subjective effects.45.5% reduction; 29.81 ± 7.58 vs. 16.24 ± 4.35 mL/100 g/min; t(29) = -10.69, p < 0.001

“Thirty experienced HVB practitioners (mean age 44.97 ± 11.80 years) underwent perfusion and resting-state fMRI to assess acute cerebrovascular and post-acute network changes.”
2

Study evidence

No significant group-level change in default mode network (DMN) functional connectivity from pre to post HVB in 30 practitioners.

“Thirty experienced HVB practitioners ... underwent perfusion and resting-state fMRI to assess acute cerebrovascular and post-acute network changes.”
Claim 7 of 8SupportedThe researchers suggest that the intensity of the experience is not simply explained by reduced blood flow, and may track more closely with changes in communication within the default mode network.View evidenceHide evidence

Why this verdict

This is appropriately hedged. The profile reports that CBF reductions were not associated with 5D-ASC ratings or ΔDMN-FC, while exploratory analyses found a DMN-FC/5D-ASC association under one preprocessing approach. The claim is supported insofar as it says the researchers 'suggest' the experience is not simply explained by reduced blood flow and 'may' track with DMN communication, though the robustness caveats remain important.

1

Study evidence

Greater decreases in DMN functional connectivity (pre → post) predicted higher 5D-ASC ratings when analyses used global signal regression, but the association was not significant without global signal regression.β = -4.88 (p < 0.05 with GSR; p = 0.75 without GSR)

“In further exploratory analyses, greater decreases in DMN FC (pre - post breathwork) predicted higher 5D-ASC rating (β = -4.88, p < 0.05) in analyses using global signal regression, though this association was not significant without global signal regression (p = 0.75).”
2

Study evidence

CBF reductions were not associated with ΔDMN-FC or with 5D-ASC ratings.

“CBF reductions were not associated with ΔDMN-FC or 5D-ASC ratings.”
Claim 8 of 8SupportedThe article says the study was relatively small, preliminary, and uncontrolled, and that larger studies will be needed to determine whether the brain changes have clinical relevance.View evidenceHide evidence

Why this verdict

The caveats align with the abstract-level profile: the sample was modest at n=30, key individual-differences analyses were exploratory, the design was within-subject rather than a randomized controlled design, and the profile notes limits on robustness and generalizability. The specific need for larger studies to establish clinical relevance is a reasonable caution given the preliminary evidence and only potential therapeutic/psychedelic-adjacent implications.

1

Study evidence

No significant group-level change in default mode network (DMN) functional connectivity from pre to post HVB in 30 practitioners.

“Thirty experienced HVB practitioners ... underwent perfusion and resting-state fMRI to assess acute cerebrovascular and post-acute network changes.”
2

Study evidence

Greater decreases in DMN functional connectivity (pre → post) predicted higher 5D-ASC ratings when analyses used global signal regression, but the association was not significant without global signal regression.β = -4.88 (p < 0.05 with GSR; p = 0.75 without GSR)

“In further exploratory analyses, greater decreases in DMN FC (pre - post breathwork) predicted higher 5D-ASC rating (β = -4.88, p < 0.05) in analyses using global signal regression, though this association was not significant without global signal regression (p = 0.75).”
Then look for missing context

Context layer

What the story left out

Important study details the story did not include.

  • HVB was accompanied by increased heart rate and respiratory rate, indicating physiological arousal alongside the CBF change.

    The paper profile identifies autonomic/respiratory arousal as accompanying the CBF reduction, but the story presentation does not mention these physiological changes.

    From Within-subject ASL perfusion fMRI during HVB (baseline vs interval of maximal subjective effects)

  • Default mode network functional connectivity did not change significantly at the group level from pre to post breathwork.

    This null group-level result is material because it limits claims that breathwork generally altered network communication. The story instead emphasizes altered communication or DMN changes without noting the group-level null finding.

    From within-subject pre-post resting-state fMRI

  • The reported DMN-FC association with altered-state intensity was exploratory and depended on preprocessing: significant with global signal regression but not significant without it.

    This is an interpretation-changing limitation for DMN-related claims. The story mentions general preliminary/small-sample caveats but does not mention that the key DMN–ASC association was exploratory and preprocessing-sensitive.

    From Exploratory regression with preprocessing sensitivity

5 things the story did carry across
  • Acute high-ventilation breathwork produced a large reduction in global grey-matter cerebral blood flow measured with ASL during maximal subjective effects: 45.5%, from 29.81 ± 7.58 to 16.24 ± 4.35 mL/100 g/min.
  • Participants were 30 experienced high-ventilation breathwork practitioners studied in a within-subject baseline-versus-peak-effects MRI design.
  • CBF reductions were not associated with ΔDMN-FC or 5D-ASC ratings, suggesting perfusion changes, network changes, and subjective intensity may be partially dissociable.
  • Subjective acute psychotropic effects and altered-state intensity were measured using self-report instruments, including an online Likert scale and the 5D-ASC.
  • General limitations include modest sample size, experienced-practitioner sample, exploratory analyses, and lack of randomized controlled evidence/generalizability to breathwork-naïve participants.
Then read the study layer

Study layer

Study at a glance

Scan the study first. Expand only the parts you want to inspect.

Pieces of work

5

Evidence read

study summary

Lead result

human in vivo

1Lead resulthuman in vivoHigh ventilation breathwork (HVB) acutely reduces cerebral perfusion (global grey-matter CBF), alongside physiological arousal, during maximal subjective effects.Within-subject ASL perfusion fMRI during HVB (baseline vs interval of maximal subjective effects)Expand

In plain English

In a within-subject ASL perfusion fMRI study of 30 experienced high ventilation breathwork (HVB) practitioners, HVB produced a large acute reduction in global grey-matter cerebral blood flow (45.5% decrease from 29.81 ± 7.58 to 16.24 ± 4.35 mL/100 g/min; t(29) = -10.69, p < 0.001) measured during the interval of maximal subjective effects, accompanied by increased heart and respiratory rate.

Key findings

  • Acute high ventilation breathwork produced a large reduction in global grey-matter cerebral blood flow measured by ASL during the interval of maximal subjective effects.45.5% reduction; 29.81 ± 7.58 vs. 16.24 ± 4.35 mL/100 g/min; t(29) = -10.69, p < 0.001
“Thirty experienced HVB practitioners (mean age 44.97 ± 11.80 years) underwent perfusion and resting-state fMRI to assess acute cerebrovascular and post-acute network changes.”
2human in vivoHVB does not produce a robust group-level change in default mode network (DMN) resting-state functional connectivity (FC) from pre to post breathwork; exploratory individual-differences analyses suggest a possible DMN-FC–ASC intensity relationship contingent on preprocessing choices (global signal regression).within-subject pre-post resting-state fMRIExpand

In plain English

Within-subject pre–post resting-state fMRI in 30 experienced HVB practitioners found no significant group-level change in default mode network (DMN) functional connectivity following high ventilation breathwork. Exploratory individual-differences analyses reported that larger pre–post decreases in DMN FC predicted greater altered-states intensity on the 5D-ASC scale when analyses used global signal regression (β = -4.88, p < 0.05), but this association was not significant without global signal regression (p = 0.75). CBF reductions measured with ASL were not associated with DMN-FC changes or 5D-ASC ratings.

Key findings

  • No significant group-level change in default mode network (DMN) functional connectivity from pre to post HVB in 30 practitioners.
  • Exploratory analysis: greater decreases in DMN FC predicted higher 5D-ASC ratings when using global signal regression (β = -4.88, p < 0.05), but the association was not significant without global signal regression (p = 0.75).β = -4.88
“Thirty experienced HVB practitioners ... underwent perfusion and resting-state fMRI to assess acute cerebrovascular and post-acute network changes.”
What this piece can’t prove
  • Exploratory nature of the DMN-FC–ASC association and its dependence on global signal regression limit conclusions about robustness.
  • Relatively small sample (n=30) may limit power to detect group-level connectivity changes or reliably estimate individual-differences relationships.

1 further detail could not be confirmed from the summary.

3human in vivoHVB does not produce a robust group-level change in default mode network (DMN) resting-state functional connectivity (FC) from pre to post breathwork; exploratory individual-differences analyses suggest a possible DMN-FC–ASC intensity relationship contingent on preprocessing choices (global signal regression).Exploratory regression with preprocessing sensitivityExpand

In plain English

Exploratory individual-differences analysis tested whether pre→post changes in default mode network functional connectivity (ΔDMN FC) predicted intensity of altered states (5D-ASC). A negative association was reported when global signal regression (GSR) was applied, but the effect was not present without GSR, indicating sensitivity to preprocessing.

Key findings

  • Greater decreases in DMN functional connectivity (pre → post) predicted higher 5D-ASC ratings when analyses used global signal regression, but the association was not significant without global signal regression.β = -4.88 (p < 0.05 with GSR; p = 0.75 without GSR)
“In further exploratory analyses, greater decreases in DMN FC (pre - post breathwork) predicted higher 5D-ASC rating (β = -4.88, p < 0.05) in analyses using global signal regression, though this association was not significant without global signal regression (p = 0.75).”
What this piece can’t prove
  • Exploratory analysis (authors label it exploratory), so findings are hypothesis-generating rather than confirmatory.
  • Dependence of significance on global signal regression indicates preprocessing-sensitive result that may not be robust.
  • Modest sample size (30) reduces power for individual-differences regression and increases vulnerability to false positives/instability.
  • Abstract does not report correction for multiple comparisons or full regression covariates/model diagnostics.
4human in vivoRelationships among perfusion changes (CBF), network changes (ΔDMN-FC), and subjective altered-state intensity (5D-ASC) suggest partially dissociable mechanisms for breathwork-induced altered states of consciousness.self-report ratings (online Likert; 5D-ASC)Expand

In plain English

The study measured subjective acute psychotropic effects during high ventilation breathwork (HVB) using an online Likert scale administered during the session, and assessed altered-state intensity immediately after the session using the 5-Dimensional Altered States of Consciousness (5D-ASC) questionnaire. These self-report measures were used as primary subjective outcomes and entered into exploratory association analyses with neuroimaging-derived metrics (ΔDMN-FC) and perfusion (CBF). An association was reported between greater decreases in DMN functional connectivity and higher 5D-ASC ratings when global signal regression was applied (β = -4.88, p < 0.05), but this association was not significant without global signal regression (p = 0.75). Reductions in cerebral blood flow were not associated with ΔDMN-FC or 5D-ASC ratings.

Key findings

  • Acute psychotropic effects were rated during the HVB session using an online Likert scale; altered-state intensity was assessed immediately after breathwork with the 5D-ASC.
  • Greater decreases in DMN functional connectivity (pre - post breathwork) predicted higher 5D-ASC ratings in analyses that included global signal regression.β = -4.88, p < 0.05 (with global signal regression); p = 0.75 (without global signal regression)
“Acute psychotropic effects were rated using an online Likert scale, ASC intensity was assessed immediately after breathwork with the 5-Dimensional Altered States of Consciousness (5D-ASC) scale.”
What this piece can’t prove
  • Abstract does not provide numeric summaries for the in-session Likert ratings.
  • Timing differences between in-session Likert measurement and immediate post-session 5D-ASC may affect comparability of subjective measures.

2 further details could not be confirmed from the summary.

5human in vivoRelationships among perfusion changes (CBF), network changes (ΔDMN-FC), and subjective altered-state intensity (5D-ASC) suggest partially dissociable mechanisms for breathwork-induced altered states of consciousness.association/correlation analyses (within-subject)Expand

In plain English

In this within-subject study of 30 experienced high-ventilation breathwork (HVB) practitioners, the authors tested whether acute reductions in global grey-matter cerebral blood flow (CBF, measured with arterial spin labeling during baseline vs interval of maximal subjective effects) were associated with post-acute changes in default mode network functional connectivity (ΔDMN-FC, from pre/post resting-state fMRI) or with subjective altered-state intensity (5D-ASC). They report no association between CBF reductions and either ΔDMN-FC or 5D-ASC ratings. An additional exploratory finding noted that greater decreases in DMN FC predicted higher 5D-ASC when global signal regression (GSR) was applied, but that this DMN–subjective association was non-significant without GSR.

Key findings

  • CBF reductions were not associated with ΔDMN-FC or with 5D-ASC ratings.
“CBF reductions were not associated with ΔDMN-FC or 5D-ASC ratings.”
What this piece can’t prove
  • Relatively small sample (N=30) for cross-modal association testing; abstract labels some analyses as exploratory.
  • Sensitivity of FC–subjective associations to preprocessing (global signal regression) limits robustness of that link.
  • Associations reported are observational/correlational (pre→post and cross-measure), so causal inference is limited.
  • Abstract does not provide full statistical details (e.g., exact tests, confidence intervals) for the null association results.
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