Anuloma Viloma Timer
A 2025 University of Sussex brain-imaging study set out to measure what happens in the brain during conscious, paced breathwork. The researchers reported visible overlap between the neural patterns produced by slow breath and patterns observed in earlier scans of people on psychedelic substances. No drugs. No plant medicine. Just breath.
The study and the Sussex broadcast write-up (ScienceDaily, 1 September 2025; sussex.ac.uk press summary) frame it carefully. They are not claiming breath is identical to a psychedelic experience. They are reporting that one specific subset of the neural signatures that researchers have used to identify a “psychedelic-like state” can also appear when a healthy adult is breathing slowly and intentionally.
That is a quiet sentence with a loud implication.
Why the headline matters
Most contemporary breathwork discourse has been pulled into one of two corners. In one corner, the wellness corner: breathwork as a calming exercise, a Calm-app fixture, something between a meditation and a stretch. In the other corner, the substance corner: ketamine, psilocybin, the various plant medicines now being studied as treatments for depression and PTSD.
The Sussex result sits in neither corner cleanly. It is suggesting that a paced, conscious breath practice can produce some of the same neural conditions that researchers are now studying drugs for. That is not a small claim. It is also not a new claim. It is just the first time the imaging itself has been pulled together this way.
The ancient name
The traditional South Asian name for the family of practices that includes slow, controlled, ratio-based breathing through the nose is pranayama. The specific technique that alternates between the two nostrils, with a controlled pause between inhale and exhale, is called nadi shodhana. In Hindi the same technique is widely known as anuloma viloma.
The pause between inhale and exhale, the held stillness that contemporary apps now label “box breathing” or “cyclic sighing”, has its own name. It is called kumbhaka. The kumbhaka is older than every modern rebrand of slow breathing. The four-count box that wellness creators teach this year is the same shape that yoga texts have described for centuries.
This matters because the Sussex result is most interesting when it is read alongside the lineage. The pattern in the brain scan is not new. The pattern in the practice is not new. What is new is the imaging, the language, and the credibility transfer.
What the practice actually looks like
A simple nadi shodhana session has three phases. Inhale through one nostril for a count. Hold the breath at the top for a count. Exhale through the other nostril for a count. Then reverse the side. The ratio is what you change to change the effect: longer exhales tip the nervous system toward rest; longer holds push the brain toward the kind of focused inward attention the Sussex researchers were measuring.
You can do this anywhere. You do not need a mat, a retreat, a teacher, or a supplement. You do need a steady ratio and enough time to settle into it. Five minutes is the lower threshold where the effects start to show up in self-report and in measurable physiological data (HRV, EEG asymmetry, vagal tone markers). Fifteen minutes is the window the Chakraborty et al. 2025 paper in Applied Psychophysiology and Biofeedback used to measure a single-session HRV change in healthy young adults.
A boring intervention with a surprising result
Most of the recent peer-reviewed work on nadi shodhana and slow nasal breathing has produced quiet, real findings. A 2025 King’s College London trial of slow nasal breathing for generalised anxiety disorder reported HRV improvement and inhibitory control gains across 135 patients. A 2026 systematic review of pranayama for mental disorders, published in Frontiers in Psychiatry, found a consistent positive direction across the meta-analysis. A 2025 randomised trial of anulom vilom added to standard hypertension care, published in Annals of Neuroscience, reported reductions in both systolic and diastolic pressure at six weeks.
The Sussex brain-imaging study lands in a slightly different register. It is not measuring an outcome on a clinical scale. It is measuring what the brain looks like during the practice. That is the part that connects to the psychedelic-research conversation.
If the imaging pattern is in the same neighbourhood as a psychedelic-state pattern, then the practice is doing something to the brain’s resting baseline that is closer to a substance than mainstream breathwork has been credited for. The Sussex team is not claiming equivalence. They are reporting a measurable family resemblance.
The careful read
A few honest caveats. The Sussex result is a press summary plus a study report; the underlying journal protocol is the load-bearing detail and is worth reading directly. “Looks like a psychedelic state” is a headline framing, not a clinical claim.
What it does change is the lay framing. Slow breath is no longer just “calming.” It is something measurable, with imaging behind it, and with a Sanskrit name.
Three days from International Yoga Day
The 12th International Day of Yoga falls on Sunday 21 June 2026. The theme is “Yoga for Healthy Ageing.” Prime Minister Modi will lead the national event at Red Road, Kolkata, with over 210 Indian missions abroad organising events at nearly 2,500 locations.
The Sussex study is a quiet, separate thread. It does not need IDY to matter. But it is a useful reminder that the practices celebrated on IDY are an old technology now being measured by a new generation of researchers.
If you have not tried it, three days from IDY is a reasonable moment to start. Five minutes of nadi shodhana. Equal-ratio breath. Eyes closed if it helps. Hold the pause at the top of the inhale if it feels stable. Notice whatever shifts.
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