Asteroseismology Meets Neurodynamics. Collective Modes as a Unified Understanding Framework Across Scales and Levels

Asteroseismology studies stellar oscillations to infer internal structure. Neurodynamics studies neural oscillations to understand brain function. Despite enormous differences in scale (10⁹ m versus 10⁻⁴ m) and medium (stellar plasma versus neural tissue), both systems obey formally similar wave equations, where natural frequencies depend on radial profiles of density (stars) or conductance (neurons). We propose that this analogy is a manifestation of the Underlying Properties Hypothesis (UPH): the same organising principles — geometry, gradients, oscillation — re‑express themselves at different levels of complexity. We derive a unified wave equation that encompasses both stellar and neural oscillations, and show how standard asteroseismic inversion techniques can be adapted as "neural seismology" to infer internal neuronal structure from oscillation spectra. Conversely, we import tools from critical‑systems neuroscience — avalanche statistics, cross‑frequency coupling metrics — to re‑interpret open problems in asteroseismology such as mixed‑mode anomalies and residual surface terms.In both directions, the emphasis is on methods that travel across domains, not on any microscopic identity between stars and brains. A radially branched geometry inspired by the starfish extends the model beyond the cylindrical approximation, connecting neuronal morphology to chiral extensions of Gradient Indeterminacy (I‑G). The framework yields falsifiable correspondences between pulsar glitch statistics and neural avalanche scaling, between stellar mixed‑mode coupling and thalamo‑cortical cross‑frequency coupling, and between dendritic spectral shifts and early neurodegeneration biomarkers. The brain and the cosmos may encode their interiors through the same class of coherent dynamical structures.