Rosacea is cutaneous vasomotor tone losing its reversibility. Putting the already-measured EDAR γ — the thermoregulation-interface organ — on the same R19 switch makes vasomotor tone a hysteretic two-lock jam: dilated when jammed ON, constricted when OFF, with a fixed state once a sustained drive crosses a lock. Rosacea (a vasodilator drive that locks the vessel dilated into fixed telangiectasia) and Raynaud phenomenon (a vasoconstrictor drive giving a reversible attack) then differ only by drive sign, with no fitted constant.
Cutaneous vasomotor tone — the neurovascular reactivity that flushes and blanches the skin — is reproduced as a hysteretic two-lock reactivity jam on the same R19 switch as the barrier and wound, running on the already-measured EDAR γ (the thermoregulation-interface organ, whose vasomotor arm is intrinsic to it) with no new γ fetched and none fitted, and with the dermal-perfusion magnitude left an inherited circulatory seam. The vessel locks dilated at an upper spinodal and constricted at a lower one and is reversibly responsive between them [V] Simulation-verified; the resting tone, reactivity gains and constrictor drives are forced regime scales [F] Forced (substrate), the clinical mappings are cited anchors [L] Cited anchor, and absolute erythema/vessel/temperature magnitudes stay open [O] Open (obstacle stated). Rosacea (a standing vasodilator drive that locks the vessel dilated into fixed telangiectasia, with a papulopustular inflammatory amplifier) and Raynaud phenomenon (a cold vasoconstrictor drive giving a reversible attack) follow as the same switch driven in opposite directions, passing an intervention-reversal battery and a three-axis opposite-property discriminant — vasodilation vs vasoconstriction, fixed vs reversible (the lock rule), vascular vs inflammatory — the layer adding no constant while the core-battery hash stays fixed.
Vasomotor tone is a reactivity jam — the same physical class, on the thermoregulation-interface organ
Every disease so far has lived on a barrier, a bond, a duct or a cycle. Rosacea lives on the cutaneous vasculature's reactivity, and the core battery had no vasomotor target — which is exactly why rosacea was held back as not-yet-modelable. This page adds that target without a new organ and without a fitted constant: it puts the already-measured EDAR γ = 1.3696 — the organ the atlas labels the thermoregulation interface — onto the same R19 switch as the barrier and wound, and reads vasomotor tone off it. The justification is anatomical: the cutaneous thermoregulatory interface has two autonomic effector arms — the sudomotor arm (sweat glands, the T5 target and the hyperhidrosis/HED diseases) and the vasomotor arm (skin blood flow, flushing). Rosacea is a dysregulation of the vasomotor arm — the vascular mirror of hyperhidrosis on the sudomotor arm — so it is intrinsic to this same organ. A vessel is read as a member of the package's jamming class the natural way round: dilated = jammed ON (s>0, flushed), constricted = OFF (s<0, quiescent/ischemic).
| Quantity | Value | Meaning |
|---|---|---|
| Master gene (reused, measured) | EDAR γ = 1.3696 | the appendage / thermoregulation-interface γ already vendored for the sweat (T5) and hair-cycle pages — the vasomotor arm is intrinsic to this organ |
| New γ fetched | no | no NCBI fetch and no fit — only a new dynamical target on the existing measured γ (the hair-cycle / adhesion pattern) |
| Spinodal | 0.6169 | substrate-derived from the same γ (sets the reactivity regime scale) |
| Healthy net vasodilator drive | -0.30 | the healthy vessel sits in the reversible middle, responsive and locked neither way (yes) |
The dermal-perfusion magnitude is not re-derived here — it stays an inherited circulatory citation (a seam variable the package imports, never re-emerges). This target adds only the vasomotor reactivity dynamics the rosacea handoff said was missing: a reactivity threshold and a hysteretic fixation. Naming that seam keeps the vascular magnitude where it lives (the circulatory package) while the reactivity dynamics lives here.
Vasomotor tone is a hysteretic two-lock switch, not a graded dial
Run as the R19 switch, the vessel does not drift smoothly from dilated to constricted. It locks dilated discontinuously once the net dilator drive exceeds the upper spinodal (a jump of about 2.03 at net drive ≈ 1.005), and locks constricted discontinuously once it falls below the lower spinodal (a jump of about 2.03 at net drive ≈ -1.005), tracing a hysteresis loop of width about 2.01. Discontinuous locking (yes) and a finite loop (yes) are the first-order signature — the simulation-verified core [V] Simulation-verified of this page, taken straight from the substrate with nothing tuned. Between the locks the vessel is reversibly responsive: it flushes with heat and constricts with cold and returns, crossing no lock. The clinical reading is immediate: an early flush comes and goes, but once a sustained drive carries the vessel past the upper lock the dilation is fixed — which is why telangiectasia does not fade when the trigger is removed, and why a partial vasoconstrictor blanches without resetting it.
The page is explicit about what it does not claim. The hysteresis shape — the two discontinuous locks, the loop, the responsive middle, and the lock rule below — is verified [V] Simulation-verified; the resting tone, the reactivity gains and the trigger/constrictor drives are dimensionless regime scales [F] Forced (substrate); the clinical mappings are cited anchors [L] Cited anchor. The absolute erythema index, vessel density, flush magnitude, digital temperature, attack frequency and involved body-surface area remain open [O] Open (obstacle stated), inheriting the vasomotor target's obstacle — a per-vessel calibration, with the perfusion magnitude itself an inherited circulatory seam. The vessel is graded on direction, discontinuity, hysteresis and the lock rule, never on a fitted magnitude.
Two vasomotor diseases are one switch driven in opposite directions
With the reactivity jam established, rosacea and Raynaud phenomenon follow as the same switch driven with opposite signs, and each established therapy is the same drive reversed — no new physics between them.
| Disease | Drive (knob moved) | Covered as |
|---|---|---|
| Rosacea | a standing vasodilator reactivity drive (lowered flush threshold; heat / alcohol / ultraviolet / spice) | carries the net dilator drive above the upper spinodal → the vessel locks dilated (fixed erythema/telangiectasia); the LL-37/Demodex amplifier on the same dilated background gives the papulopustular subtype; anti-inflammatories clear the papules, brimonidine blanches transiently, laser resets the fixed vessels |
| Raynaud phenomenon | a cold / stress vasoconstrictor drive | carries the net dilator drive negative into the constricted/ischemic basin → a reversible white-blue-red digital vasospastic attack (it crosses no lock); rewarming and a vasodilator / calcium-channel blocker abort it; the fixed digital-ischemia / ulcer state is the secondary (connective-tissue-disease) seam |
Rosacea: a standing dilator drive locks the vessel dilated
Rosacea is a standing vasodilator reactivity drive — a lowered flush threshold under heat, alcohol, ultraviolet and spice. Early on, a transient flush is a sub-lock excursion that still returns (yes); but a sustained drive carries the net dilator drive past the upper spinodal, so the vessel locks dilated (yes) and the dilation is fixed — persistent erythema and telangiectasia (yes, dilation depth 1.00). The cathelicidin LL-37 / Demodex inflammatory amplifier on the same dilated background gives the papulopustular subtype (yes). The therapeutic structure falls straight out of the hysteresis: anti-inflammatory therapy (metronidazole / ivermectin / azelaic acid / doxycycline) clears the papules (yes) but leaves the vascular background (yes); a vasoconstrictor (brimonidine) blanches the skin transiently but, because a partial constrictor leaves the net drive above the lower lock, it does not reset the fixed vessels (yes — still dilated); only laser / intense-pulsed-light physically resets the telangiectasia (yes), a structural reset exactly like deroofing for a hidradenitis tract.
Raynaud phenomenon: the opposite drive, and a reversible attack
Raynaud phenomenon is the opposite sign on the same switch: a cold or stress vasoconstrictor drive carries the net dilator drive negative, deepening the vessel into the constricted/ischemic basin (yes, constriction depth 1.00) and producing the white-blue-red digital attack. Primary Raynaud is a reversible excursion in the resting basin — it crosses no lock — so it reverses on rewarming (yes), and a vasodilator or calcium-channel blocker (nifedipine) aborts an attack (yes). The contrast with rosacea is the page's sharpest result: rosacea's drive crosses its lock, so its dilation is fixed; primary Raynaud's stays short of its lock, so its constriction reverses. The fixed digital-ischemia / ulcer state is a downstream structural change of secondary Raynaud with connective-tissue disease — an immune / rheumatology sibling-package seam, named not modeled here.
The discriminant: opposite vasomotor diseases from opposite drive signs
As with the static diseases, the hair cycle, the sebaceous duct and the adhesion bond, the decisive evidence is that clinically opposite behaviours fall out of the same switch driven differently, with no constant changed between them — here, driven in opposite directions on one vasomotor switch.
| Axis | One pole | Opposite pole | Reproduced |
|---|---|---|---|
| Direction | vasodilation (rosacea: drive above the upper spinodal) | vasoconstriction (Raynaud: drive negative into the constricted basin) | yes |
| Reversibility | fixed telangiectasia (rosacea: the drive crosses the upper lock) | reversible vasospasm (primary Raynaud: stays short of the lock) | yes |
| Vascular vs inflammatory | erythematotelangiectatic (vascular, the dilation/fixation story) | papulopustular (the inflammatory LL-37/Demodex amplifier) | yes |
All three opposite pairs reproduce (yes). That one vasomotor switch yields a fixed-dilation disease and a reversible-constriction disease, a vascular and an inflammatory rosacea pole, and reversibility governed by a single lock rule — from the drive sign alone, on one reused EDAR γ with no new parameter — is the strongest internal evidence that these vasomotor diseases are reactivity-jamming dynamics, not bespoke fits.
Grades and reproducibility
Every mechanism here is a simulation-verified shape or sign [V] Simulation-verified — the two discontinuous locks, the hysteresis loop, the responsive set-point, the vasodilation/vasoconstriction direction, the reversible-vs-fixed lock rule, the papulopustular amplifier and the brimonidine-vs-laser hysteresis. Every clinical mapping rests on a cited anchor [L] Cited anchor. The resting tone, reactivity gains and constrictor drives are forced regime scales [F] Forced (substrate). Every absolute magnitude is open [O] Open (obstacle stated) — erythema index, vessel density, flush magnitude, digital temperature, attack frequency, body-surface area — inheriting the vasomotor target's obstacle (a per-vessel calibration), with the dermal-perfusion magnitude an inherited circulatory seam, not calibrated here. No disease introduces a new constant; each is a signed vasomotor drive on the one switch, and no new γ is fetched.
The vasomotor pipeline is deterministic on its own terms: two independent runs hash to an identical SHA-256, separate from the core battery, the pathology layer, the hair-cycle layer, the sebaceous layer and the adhesion layer. Crucially, adding this target does not touch the core T1–T5+oncology battery, whose result hash is unchanged at 1fb59f556e01….