Migraine as Paroxysmal Sensory Decoherence: Cortical Spreading Depression, Thalamo-Cortical Gain Failure

Migraine ranks among the most prevalent and disabling neurological disorders worldwide. It is classically defined by recurrent, stereotyped attacks of moderate-to-severe unilateral head pain accompanied by sensory hypersensitivities (photophobia, phonophobia, osmophobia, allodynia) and, in a subset of patients, a preceding aura of transient neurological disturbance. This paper proposes a formal reconceptualization of migraine within the Informational Nosology framework as "Regime B" — Paroxysmal Sensory Decoherence — a state in which the brain's precision-weighting and sensory-gating architecture undergoes a threshold-triggered collapse, contrasted with the state-space collapse dynamics characteristic of Epilepsy ("Regime A"). The framework integrates cortical spreading depression, thalamo-cortical gain failure, and trigeminovascular system activation (including CGRP signaling) into a unified dynamical-systems formalization of the migraine attack's onset, propagation, and resolution. By treating sensory constraint failure as an organizational phenomenon rather than a purely vascular or nociceptive event, the framework offers a coherent systems-level interpretation of the attack's stereotyped architecture, its threshold behavior, and its protracted recovery dynamics. Part of the Informational Monism / Informational Nosology series (Portal IV), developed within a unified mathematical program for neurological and psychiatric regime classification. Keywords: Migraine, Paroxysmal Sensory Decoherence, Cortical Spreading Depression, CGRP, Neurology; Neuroscience; Biophysics; Informational Nosology