Epilepsy — the over-synchronisation pole

Epilepsy is the over-synchronisation pole of the engine's synchrony axis: an excitatory bias drives the order parameter to the over-sync ceiling and the selective gate collapses, so every assembly ignites — the ictal state. An inhibitory anticonvulsant-class push reverses it and raises the seizure threshold. The ictal time-course is owed to a state-switching layer. efficacy=0.

The over-sync failure mode has run quietly through the whole framework: it is the ceiling the θ-cap must stay below, the boundary every coupling result respects. This chapter makes it a primary module. Epilepsy is the over-synchronisation pole of the engine's synchrony axis — the global Kuramoto order parameter R on the measured ephaptic kernel, plus the R19 ignition gate. An excitatory/disinhibitory E/I bias drives R monotonically up toward the over-sync ceiling; past a critical bias the selective single-winner gate collapses and every candidate assembly ignites — the ictal state. On one axis the conditions line up: autism-T (under-ignited) < health (selective) < schizophrenia (aberrant) < epilepsy (all ignited). An inhibitory / threshold-raising anticonvulsant-class push reverses it and raises the seizure threshold. The static susceptibility is characterised here; the ictal time-course is owed to a state-switching layer. efficacy = 0.

epilepsy = the over-synchronisation pole; the ictal state = collapse of the selective gate = excitatory bias drives R to the over-sync ceiling and all assemblies ignite; an anticonvulsant reverses it and raises the threshold — epilepsy is the over-synchronisation pole of the engine's synchrony axis (the global Kuramoto order parameter R on the measured ephaptic kernel, plus the M3 R19 ignition gate). An excitatory/disinhibitory E/I bias raises R monotonically toward the over-sync ceiling (0.422 > health 0.390); past a critical bias (+0.3) the selective single-winner gate collapses and EVERY candidate assembly ignites — the ictal state, a loss of GATING (Axis-A firewall: a mechanism boundary, not a claim about ictal experience; consciousness_claim=0). On one axis: autism-T (under-ignited) < health (selective) < schizophrenia (aberrant, some irrelevant) < epilepsy (all ignited). An inhibitory / threshold-raising anticonvulsant-class push moves R back down and restores the gate — it raises the seizure threshold by moving the operating point away from the over-sync ceiling (the same ceiling the θ-cap must stay below, §20). The static susceptibility is characterised; the ictal time-course is OWED to a state-switching layer (E2). efficacy=0; not medical advice. [V mech]. this chapter

schizophrenia = the over-ignition mirror of autism-T on the same R19 axis = excitatory bias lowers the fold → aberrant ignition; antipsychotic restores it and worsens autism-T — on the one shared ignitability axis (the M3 R19 fold = spinodal(g) = 2(g/3)^1.5 = 0.3849, measured-grounded), schizophrenia is the opposite pole from autism-T: a disinhibitory/excitatory E/I bias LOWERS the fold (ignition threshold 0.245 vs health 0.395) so weak, in-health-sub-fold assemblies (candidates 2,3) now ignite — aberrant salience with no loss of the relevant ones — where autism-T's inhibitory bias RAISES the fold and loses relevant ignitions. The pair (ignition-direction, aberrant-vs-lost) separates HEALTH / AUTISM-T / SCHIZOPHRENIA uniquely. A uniform gain-reducing / threshold-raising antipsychotic-class push restores the healthy selective set (4,5) and worsens autism-T; the gain-raising stimulant that helped autism-T worsens schizophrenia — one handle, opposite signs at the two poles. The therapeutic sign aligns with sleep-need (arousal down), the mirror of autism. Which pole a given psychosis is, is OWED [O]. efficacy=0; not medical advice. [V mech]. canonical §24

The over-sync axis

The engine's synchrony is set by its effective coupling, and an excitatory/disinhibitory E/I bias raises that coupling. Sweeping the bias up, the global order parameter R climbs monotonically — 0.390 at health, 0.399, 0.406, 0.411, and on up to a ceiling at 0.422 where the network saturates into near-total phase-lock. This is the single most direct dynamical fit of any condition in the atlas: hypersynchrony is not a new mechanism bolted on for epilepsy, it is the framework's own failure mode, the thing every other result was built to stay clear of. Epilepsy is simply that failure mode made the object of study.

The ictal state is a collapse of the selective gate

Synchrony rising is only half of it. The functional signature of a seizure is the loss of selection. In health the R19 gate is a single-winner: of six candidate assemblies, only the two genuinely driven ones ignite. As the excitatory bias rises the gate leaks — first three ignite, then five — and past a critical bias (+0.3) it collapses entirely: all six ignite at once. There is no winner; the selective gate that lets the brain hold one thing at a time is gone. That total recruitment is the engine's image of the ictal transition. It is worth being exact about what this is and is not: the collapse of gating is a mechanism boundary, not a claim about ictal experience (Axis-A firewall; consciousness_claim = 0). The model speaks to the synchrony and the selection, not to the felt or unfelt quality of a seizure.

One axis, four conditions

The atlas's organising move is to put look-alike conditions on a shared axis, and the synchrony axis now carries four states in order. Autism-T sits below health: an inhibitory bias, under-ignited, the gate too narrow (only the strongest assemblies ignite). Health is the selective middle: two of six. Schizophrenia sits above health: a disinhibitory bias has lowered the ignition fold so some irrelevant assemblies leak through — aberrant but partial. Epilepsy is the ceiling: every assembly ignited, the gate gone. autism-T < health < schizophrenia < epilepsy, one axis, four operating points. The over-sync ceiling that bounds this axis is the very same ceiling the θ-cap operating principle (§20–21) had to respect — the distance an anticonvulsant enlarges is the distance an excitatory shift closes.

The anticonvulsant direction, and what is still owed

Because epilepsy is the over-sync pole, the corrective sign is unambiguous. From an ictal bias, an inhibitory / threshold-raising push — the GABAergic anticonvulsant-class direction — moves R back down (0.411 → 0.406 → 0.399 → 0.384 → 0.366 as the push strengthens) and restores the selective gate, dropping the ignition count from six back toward the healthy two. Mechanistically it raises the seizure threshold: it moves the operating point away from the over-sync ceiling, so a larger excitatory excursion is needed to lose the gate. This is sign-only — a direction, not a dose or an efficacy. And one thing is explicitly owed: this module characterises the static susceptibility — how close the operating point sits to the ceiling, and which way each handle moves it — but not the onset dynamics. The actual ictal transition, the moment a brain switches from interictal to seizing and back, is a movement between attractors over time, and that needs the state-switching layer (E2) the roadmap reserves for the episodic disorders. The susceptibility is here; the time-course is the next layer. Every value is an in-silico coupling state, not a clinical measure — efficacy = 0; this is a mechanism-level result about epilepsy as represented in the VP framework, not medical advice, a diagnosis, a treatment protocol, or a cure.