Anuloma Viloma Timer
Twenty-two people breathed at six breaths a minute while a mild electrical current pulsed through their outer ear, timed to every out-breath. On another visit they did the same thing with a sham device clipped to the earlobe. Their heart rate variability came out the same both times.
That is the 2023 crossover study by Szulczewski, D’Agostini and Van Diest in Applied Psychophysiology and Biofeedback, and it is the most useful result we looked at this week. Not because it is big (it is not) or final (the authors say plainly it is not), but because of the question it asks. Much of the wellness conversation around the vagus nerve treats slow breathing as a weak, home-made version of a device. This study did the reverse. It put the device on top of the breath and measured what it added.
In this sample, with these settings, it added nothing.
That turned out to be the shape of the whole week. Every day we looked at something layered on top of slow breathing: a gadget, a brain theory, a fresh name for an old rhythm, a full moon, an empty stomach, a seal’s record dive. Each time we took the layer away, the same plain thing was still standing. A slow count, with an unhurried breath out.
The add-on test
The design is worth a closer look, because it is the right way to ask whether an extra earns its place. The stimulation is called transcutaneous auricular vagus nerve stimulation, usually shortened to taVNS. It sends a small current through parts of the outer ear that carry a branch of the vagus nerve. Here it was gated to the exhale, so it worked with the breath rather than against it. The sham went on the earlobe, an area not thought to carry that branch. Each person did both sessions, in crossed order, so each served as their own comparison.
The researchers measured the standard markers of vagally mediated heart rate variability: RMSSD (the beat-to-beat change in heart rate), the average interval between beats, and heart rate variability power at the breathing frequency. Using both conventional and Bayesian statistics, they found no difference between real and sham stimulation on any of them. They note that earlier taVNS studies on heart rate variability were inconsistent to begin with, and that the combination was tried in the hope of a synergy. In these 22 people, the synergy did not appear.
The caveats are real. One small study, single sessions, one set of stimulator parameters. It does not show that ear stimulation never does anything. It shows that during slow breathing at 0.1 Hz, this setup did not add anything measurable.
Part of the reason may be that the breath had already done most of the work. A 2022 systematic review and meta-analysis by Laborde and colleagues in Neuroscience and Biobehavioral Reviews pooled 223 studies and found voluntary slow breathing linked to higher vagally mediated heart rate variability, both during and after practice. A much smaller 2018 study in Psychosomatic Medicine, just six adults, went further: when the researchers blocked parasympathetic activity with medication, the rise in low-frequency heart rate variability seen during slow yogic breathing nearly disappeared. The authors concluded that rise is almost entirely vagal. Six people is very few. But put the three papers together and the picture is coherent: slow breathing already reaches the vagus, so a device layered on top has little room left to add.
Subtract the brain story
Early in the week we traced the popular claim that the left nostril feeds the right brain back to its small origins. The scans this week turned up evidence pulling in both directions. Work from the Auckland University of Technology, reported in 2022, linked right-nostril breathing with higher arousal and left with a calmer state, while a small University of Milan study of 20 people reported the opposite. A 2025 randomised trial of 90 adults, published through SCITEPRESS, compared ten minutes of left-nostril, right-nostril and unstructured breathing, and reported different effects for each side. It is a conference paper and we have not verified its figures, so we are not quoting them.
The fair summary is that which nostril does what is an open question. The Global Wellness Institute’s 2026 Breathe Initiative trends note that practitioners are asking for real science rather than pseudoscience, and this is exactly where that request bites.
Now subtract the hemisphere claim and look at what is left. A 2024 systematic review and meta-analysis by Nam and colleagues in Complementary Medicine Research pooled six randomised trials of alternate nostril breathing, about 525 participants, and found systolic blood pressure lower on average than in control groups (supplementary record). The trials varied a great deal, enough that the authors urge careful interpretation. Still, those were people practising a slow, even, alternating breath, repeatedly, over weeks. Nobody needed a theory about hemispheres for that result to show up.
Subtract the new name
Two of this week’s pieces were about lineage, and they made the same point from different angles. Six breaths a minute is taught today as resonance or coherent breathing. A long exhale is taught as cyclic sighing. Both are presented as recent findings. Both are rhythms the hatha yoga manuals were already counting.
The Gheranda Samhita, a 17th-century manual, gives the classic pranayama ratio as 1:4:2: in for one unit, hold for four, out for two. Take out the hold and you are left with a breath out that lasts twice as long as the breath in. Count four in and six out and each breath takes ten seconds, which is six breaths a minute. The rhythm comes with the count. The name came later.
Even the modern tools point back to the count. A 2022 paper in the Journal of Clinical Medicine describes slow-paced breathing with heart rate variability feedback as a non-invasive way for people to influence their own vagal activity. The feedback screen is a guide. What it is guiding you towards is a pace.
Keep the ritual, for a different reason
Not every layer should go. The week opened with Sharad Purnima, the autumn full moon, and with the old instruction that nadi shodhana starts and ends on the left nostril, the side the Hatha Yoga Pradipika links with the moon. There is no evidence that finishing on the left calms you more than finishing on the right, and we do not claim it.
But that instruction is not a claim about your physiology. It is a structure. Starting and ending on the same side gives every round a clear beginning and end, so you know where you are without counting rounds out loud. That is worth keeping. The useful test is not “is this old?” but “does this help me hold the count?” A bookend does. A theory about your hemispheres does not.
Subtract the hold, most days
The last two daily pieces were about what to leave out. On a fast day, the advice was to keep the practice and drop the demanding parts: no breath holds, no fast bellows breathing such as bhastrika or kapalbhati, and always sitting down. The week closed with a hooded seal, an animal built to hold its breath for long dives, and a reminder that animal records are not targets. A human hold, if you do one at all, should be short, timed and seated, never in or near water, and never after fast breathing.
Both pieces arrive at the same place. The foundation of the practice needs no hold. The hold is something you can add later, carefully, on top. It is not the active ingredient.
What this means for your next session
It is worth being honest about the ceiling. A 2025 systematic review and meta-analysis of pranayama for mental health conditions in Frontiers in Psychiatry found short-term benefit when it was added to usual care, but rated the risk of bias as high, found the samples small, and said pranayama should not replace standard treatment. Slow breathing is a good daily practice. It is not a cure.
With that in mind, here is the subtracted version, the session with nothing left to take away:
- Sit down. Upright on a chair or cushion, shoulders loose.
- Close the right nostril and breathe in through the left for four.
- Switch and breathe out through the right for six.
- Breathe in through the right for four, then out through the left for six. That is one round, starting and ending on the left.
- Keep going for five minutes. At four in and six out, you are breathing six times a minute.
- No holds. Leave them out for the first few weeks.
- Stop if you feel lightheaded and breathe normally. If you have a heart or blood pressure condition or are pregnant, check with your doctor before adding holds.
If four and six feels like a stretch, use three and five, or four and four on a fast day. The point is a count you can keep without strain.
Then try a small experiment. For one week, drop every extra. No tracker to watch, no device, no theory about which side of your brain is doing what. Just the count, five minutes a day. If you notice no difference at the end of the week, you have lost nothing. If you feel steadier, you know which part was doing the work. And remember the blood pressure trials ran for weeks, so give the practice that long before you judge it.
The one extra worth keeping
If there is one thing worth adding on top of the breath, it is something that holds the count for you, so your attention can stay on the breath instead of on arithmetic. Prayer beads did that job for centuries. A timer does it now.
Anuloma Viloma Timer is free on the App Store, no subscription necessary. Set four in and six out, sit down, and let the count be the whole practice.