Meditation as Wakeful Relaxation: Unclenching Smooth Muscle (26/30)

I'm writing 30 posts in 30 days at Inkhaven. This is number 26.

The frontier of my meditation practice is exploring it as wakeful relaxation. This is how my meditation teacher, Roger Thisdell, framed it for me recently. People often treat relaxation and wakefulness as two opposites: relaxation as a drowsy and dull, wakefullnes as sharp and jittery. But the two can co-exist.

Over the last two weeks I’ve been actively trying to relax during meditation. And goddamn it, folks, this is hard. I am constantly spasming in different ways. There is a lot of tension in my body and my experiential field.

Relaxation is this game of whack-a-mole: relaxing one area of my body causes tension to pop up somewhere else. Proper relaxation requires coordinating mind and body in ways that’s not unlike learning to dance.

The thing is, intentional relaxation brings anxiety and fear. Sometimes it’s about past experiences. Sometimes it’s the stress of publishing daily — I’m currently doing Inkhaven, a 30-day writing workshop where you must publish a 500+ words post daily or they kick you out.

To get to each progressively deeper levels of relaxation, I have to be fairly equanimous. That usually means being a bit overwhelmed with emotion. Muscle tension seems to guard against feeling stress. It’s not just “bracing for impact” — something more complex is going on.

When I manage to relax more completely, something shifts in my experience. I get less reactive and less neurotic — I generate fewer negative “what if” scenarios. Interfacing with people feels less effortful too: e.g. it becomes easier to switch from planning my day to chatting with a friend who walks by.

It’s almost as if my default stance on reality changes. What’s going on?

Michael Edward Johnson on Stances

There’s something in vasocomputation I’ve been calling a “stance” or way of feeling — stances are essentially discrete patterns of muscle tension (primarily vascular tension) that we can jump into and which offer specific affordances. The girl in this video is a great example: she goes from her default stance, to professional-calm, back to default (with a big release of tension)

Vasocomputation’s basic thesis is “vascular clenches stabilize neural patterns” — patterns of muscle tension will set certain aspects of phenomenology as constants and others as variables. I.e. every stance has a certain internal feeling that defines the stance and as long as you hold this feeling, you “hold frame” — if you lose the feeling (i.e. if this core pattern of stabilizing tension shifts), you break frame.

[continued on twitter]

Let’s unpack this.

The whole body is a computer: it’d be wasteful for evolution to only use the brain for computation when other systems could take part too. Muscle tension constrains and stabilises neural patterns. I picture this as some regions of “thought–feeling space” becoming less accessible — like clamping some pages in a book, or putting an overly active dog on a leash in a crowd so it doesn’t run away.

Mike says that this tension is primarily vascular — in the smooth muscle that lines blood vessels. The word “primarily” means that working with the “regular” skeletal muscle can be productive, but we could do much better by relaxing smooth muscle.

All these blood vessels are lined with smooth muscle. So. Much. Muscle.

Clenched smooth muscle

Smooth muscle works very differently from skeletal muscle — it’s not under direct conscious control. You can consciously decide to flex your bicep, but you can’t decide to constrict your left renal artery.

If Mike is right, then the situation is cursed: there is a system in the body we have no direct access to, and it heavily influences our conscious experience.

What’s worse is that smooth muscle can also form energetically inexpensive “latches” — patterns of contraction that persist as stable, semi-permanent “knots” in the body’s tissues. A skeletal muscle is (roughly) either “relaxed” or “tensed.” Smooth muscle has three interesting modes: “relaxed,” “tensed,” and “latched.”

Mike’s hypothesis is that smooth-muscle latches can persist long-term — for months and years, depending on which prediction or mode of action they’re stabilising. He outlines this in Principles of Vasocomputation: A Unification of Buddhist Phenomenology, Active Inference, and Physical Reflex:

Latches can persist for minutes, hours, days, months, or years (depending on what prediction they’re stabilizing), and the sum total of all latches likely accounts for the majority of bodily suffering. If you are “holding tension in your body” you are subject to the mechanics of the latch-bridge mechanism. Migraines and cluster headaches are almost certainly inappropriate VSMC latches; all hollow organs are surrounded by smooth muscle and can latch.

He also claims that latching for months and years is possible because this tension does not require ongoing energy. So far I haven’t been able to independently verify this strong version of the claim. Textbooks say the latch state requires “low energy consumption,” not “no energy”, and the timescale usually given is “hours,” not years.

For example:

1. Brant B. Hafen; Bracken Burns in Physiology, Smooth Muscle:

The mechanism that allows the smooth muscle to maintain high-tension at low energy consumption; termed the latch state

2. Charles Asbury in “Muscle Physiology”:

This so-called latch (or latch-bridge) behavior is thought to help smooth muscles maintain luminal pressures (e.g., in the vasculature) more economically than they would otherwise, by allowing them sustain tension over long times while using less ATP.

3. Chapter 7: Excitation of Skeletal Muscle - Neuromuscular Transmission (PHYSIO 101)

Once smooth muscle has developed full contraction, the amount of continuing excitation can usually be reduced to far less than the initial level even though the muscle maintains its full force of contraction. Further, the energy consumed to maintain contraction is often minuscule, sometimes as little as 1/300 the energy required for comparable sustained skeletal muscle contraction. This mechanism is called the “latch” mechanism.

The importance of the latch mechanism is that it can maintain prolonged tonic contraction in smooth muscle for hours with little use of energy. Little continued excitatory signal is required from nerve fibers or hormonal sources

Still, from my meditation practice it’s pretty clear that skeletal muscle tension plays an important role. It would be surprising if evolution recruited only one type of muscle for computation without also recruiting the other. So while I don’t yet buy into the full story, it seems highly plausible that latches play some role in the way Mike describes. Perhaps even if individual latches don’t persist for years, they can unclench and re-clench in similar patterns, with similar effects.

EDIT: Mike posted a great response to these concerns on twitter and it makes me more confident in the model.

Meditative practice for unclenching

So how do you actually relax, given all this? Mike gives some advice in “Principles of Vasocomputation”:

Sauna + cold plunges are an effective way to force the clench-release cycle and release latches; likewise, simply taking time to feel your body and put your attention into latched tissues can release them. Psychedelics can force open latches.

I’m not sure why putting attention on a body part would cause unlatching when smooth muscle isn’t under conscious control. Perhaps the mechanism is indirect: you highlight a set of neural patterns in attention, and that in turn changes autonomic and vascular signalling in the associated territory.

If this works, there must be some way to tune our meditation methods specifically for relaxing smooth muscle. One guess: ultra-slow body-scan Vipassana combined with deliberate clench-release cycles, e.g. contrast showers or sauna + cold, using awareness to track exactly how and where the body grips and lets go.

This is the direction I intend to take my practice into. If you have other ideas — let me know in the comments.

Links

1. Michael Edward Johnson: Principles of Vasocomputation: A Unification of Buddhist Phenomenology, Active Inference, and Physical Reflex

2. Mike Johnson: In the beginning there was sensation

3. Mike Johnson: a video recording of a talk on vasomputation

4. Mike Johnson: Vasocomputation suggests that imagination is essentially tension-based

5. Hinterlander: meditation as mental stretching

6. Mike Johnson: The idea that sports physiology has a lot to say about how to train ‘mental muscles’ (which are literal muscles) seems super generative