Sympathetic Harmonic Resonance Framework (SHRF) Hypothesis for Dementia Aetiology: Coherence Debt, Coupling Failure, and Clearance-Limited Network Collapse

abstract Dementia is a clinical syndrome arising from heterogeneous neuropathologies (e.g., Alzheimer’s disease, vascular brain injury, Lewy body disease) that converge on progressive failure of distributed neural computation. This paper applies Sympathetic Harmonic Resonance Framework (SHRF) reasoning: the brain is treated as a multi-scale, energy-limited, phase-coupled resonant network whose cognitive capacity depends on maintaining task-appropriate coherence while preserving flexibility and nightly reset/clearance. In this view, ``dementia'' emerges when chronic increases in phase noise, reductions in effective coupling, and impaired physiological resets create a growing \emph{coherence debt} that the system can no longer service. Mainstream hallmarks (amyloid-$\beta$, tau, vascular lesions) are not rejected; instead, SHRF proposes a unifying dynamical layer that explains why diverse risk factors and pathologies produce similar clinical endpoints: gradual collapse of achievable network coherence under demand, with compensatory maladaptive stabilization (rigid attractors, hyperexcitability, and deposition). We derive falsifiable predictions using EEG/MEG phase metrics, sleep/clearance proxies (glymphatic physiology), vascular variability measures, and sensory-entrainment restoration (hearing/vision correction). The aim is a testable synthesis that bridges neuropathology and systems dynamics without asserting that resonance concepts supplant established molecular mechanisms.