The Coherence Stack— UPDATE

An update to yesterday's post

So I thought I’d stumbled onto something novel yesterday (post). Turns out Levin and McGilchrist have already been talking. McGilchrist commented on Levin’s work in 2025, calling it “fascinating,” and said he agreed that something “ingresses into the phenomenal world and finds expression there.”

Good. That’s the right direction. But the core problem remains: where does memory actually live?

Levin can measure bioelectric signals across the body. He can manipulate them and change what cells “remember” about body structure. But when you ask him where that information is stored, he calls the mechanism “opaque.” Neuroscience has chased the engram for a century and never pinned it down either.

Here’s the piece that might still be new:

The Penrose-Hameroff theory proposes that quantum coherence in microtubules is the substrate, where information actually persists. The problem has always been temperature. Critics say quantum states can’t survive the thermal chaos of a living body. That objection has kept the theory marginal for thirty years.

But a paper came out in November 2025 (Zhang et al., Nature Materials, doi:10.1038/s41563-025-02413-5) demonstrating something called the Brownian spin-locking effect. In colloidal suspensions, coherent quantum properties, spin polarization specifically, persisted and propagated through thermally disordered systems. Not by being isolated from the noise. By moving through it via spin-orbit coupling.

That’s optical physics, not biology. The jump to microtubules is an analogy at this point, not a demonstration. But if microtubules have the right structural properties for similar spin-orbit effects, you’d have a mechanism. Quantum memory that survives body temperature.

And then the rest of the stack starts to connect:

Levin’s bioelectric signals would be the downstream readout, what you can measure when the deeper quantum patterns express themselves across cell networks. McGilchrist’s hemispheric differences would result in different access patterns to the same underlying field. The right hemisphere reading it more directly, and the left hemisphere compresses it into sequences.

The brain wouldn’t be where memory is stored. It would be where the mesh gets dense enough, more microtubules packed together, to read and write complex patterns at high bandwidth. Every cell maintains coherence to stay aligned with the whole. The brain is just the densest node.

I’ll be honest about how speculative this is.

Penrose-Hameroff remains contested after three decades. The Brownian spin-locking paper is about light scattering, not tubulin. Nobody’s checked whether microtubules can support similar spin-orbit coupling. The claim that bioelectricity is the “readable expression” of a quantum substrate is a hypothesis, not a finding. You’d need to show that disrupting quantum coherence disrupts bioelectric patterns before the bioelectric changes show up, that the quantum layer is actually upstream. And framing coherence-maintenance as “observation” borrows from one interpretation of quantum mechanics that not everyone accepts.

That’s a lot of speculative joints. Four separate frameworks, each with its own uncertainties, connected by analogies that haven’t been tested.

What would strengthen it: evidence that microtubule structure supports spin-orbit coupling, an experiment showing quantum disruption precedes bioelectric disruption, someone running the actual math on tubulin.

What would kill it: proof that microtubules can’t support the relevant coupling, definitive evidence that Levin’s bioelectric memory is purely classical, or a better explanation for the engram problem that doesn’t need quantum coherence at all.

The Brownian spin-locking paper is two months old. As far as I can tell, nobody in consciousness research has connected it to the decoherence problem yet. That window won’t stay open forever.

Odds are, with this many dependencies, the hypothesis is wrong. But working through it would generate good science either way. You’d learn something at each joint.

I’m at a stealth AI startup and a hopeless jigsaw puzzle addict. This won’t be my focus. If you’re a researcher with the credentials and this structure looks worth testing, run with it, and have fun.