How the model links, step by step, the proposed origin of the PMCHS terrain to its branches of observable consequences — mast cells, interoceptive hypoesthesia, behavioral regulation, archaic reflexes.
The currently favored starting point is no longer generic perinatal trauma, but something more specific: an early rupture of safety and attachment — for example, repeated infant distress left unanswered, which "teaches" the developing nervous system that adults are not reliable. This hypothesis replaces an earlier reading of the model, where non-integrated archaic reflexes were considered the starting point (see Model evolution for the detail of this change).
The locus coeruleus (LC), the brain's main noradrenergic nucleus, becomes in the current model the central relay between the early attachment rupture and the full set of observable consequences of the PMCHS terrain.
A hyperactivated LC continuously releases noradrenaline in the brain and periphery — a chronic alert state from which, according to the current model, the four branches detailed below arise. See the full diagram of this architecture.
Chronic noradrenaline activates mast cells' β-adrenergic receptors and durably lowers their degranulation threshold — linking the LC to the ERα/GPR30 → histamine/LTC4 → HMGB1 → RAGE estrogenic amplification loop.
See the model's pillars →Chronic excess histamine desensitises hypothalamic H1 receptors, reducing the body's ability to perceive its own homeostatic signals (thirst, satiety, fatigue, pain).
See the GIH detail →Dissociation and fawning (appeasement) responses: adaptive strategies of a nervous system that has remained hypervigilant since early childhood. Still lightly documented on the site — to be developed further.
Now one downstream branch among others — no longer the model's starting point. The full detail of the LC → amygdala → mast cell cascade remains developed on its own page.
Explore the full cascade →Alongside the LC node, a self-sustaining loop locally amplifies mast cell activation: ERα/GPR30 (estrogen signaling) triggers mast cell activation, which releases histamine and LTC4, which induces the release of endothelial HMGB1, which reactivates the mast cell via its RAGE receptor — closing the loop independently of a new triggering signal. This mechanism specifically concerns the role of estrogen in tissue inflammation, in particular in the pathogenesis of lipedema and obesity — distinct from the transgenerational cumulative burden detailed below, which is a different kind of mechanism.
Main sources: Witts EC et al. Curr Biol. 2023, DOI: 10.1016/j.cub.2023.08.085 · Berridge CW & Waterhouse BD. Brain Res Rev. 2003 — on the role of the locus coeruleus in mast cell activation via the β-adrenergic pathway. The complete reference list is available on the References page.
Distinct from the estrogenic loop — a local mechanism — a second, transgenerational mechanism may explain the worsening of the PMCHS terrain from generation to generation, through the accumulation of four factors:
Fetal microchimerism closes the loop onto the next generation: semi-allogeneic fetal cells (LysM+/CD11c+ subpopulations) persist in maternal tissues for decades and may directly influence the immune and mast cell programming of the next child — a non-epigenetic transmission pathway that adds to the first two. See the full diagram of this cumulative burden.