Axial Biotensegrity and Trans-Nervous Hydro-Mechanical Forcing: A Macro-Scalar Rheological Model of Peripheral Cerebrospinal Fluid Continuum in Human Cognitive Engineering (HC-E)

Background: Classical neuroanatomical models evaluate somatosensory neuromodulation through the localized, discrete activation of membrane-bound mechanoreceptors. However, recent milestones confirming continuous cerebrospinal fluid (CSF) translocation into the perineurium, endoneurium, and distal axoplasm of the peripheral nervous system (PNS) demand a transscalar paradigm shift. Human Cognitive Engineering (HC-E) models posit that long-range sensory coordination operates via an integrated hydro-mechanical network rather than isolated bioelectric transduction. Objective: This paper formalizes the mathematical and rheological framework of the Neuro-Hydraulic Axial Reflex, providing a macro-scalar model of systemic entrainment between upper cranial-lingual nodes and lower plantar matrices without relying on microscopic protein-gating dependencies. A key operational node is the Myodural Bridge (MDB), which acts as the central regulator of spinal hydro-mechanical compliance. Methods: A fluid-structure interaction (FSI) model was developed to analyze the propagation of axial pressure pulse waves through the endoneurial fluid continuum. The model parametrizes a bimodal cross-axis mechanical input (35 s micro-percussion @ 2.1 Hz coupled with a 10 s terminal static compression @ 1.0–1.5 N) applied to high-density orofacial and submental fascial boundaries, following an ionic-protonic tissue priming phase. This configuration is cross-referenced with the 2-Minute Ultraslow Cinematic Protocol (< 1°/second) for suboccipital dural decompression. Results: Continuum mechanics and dimensional coherence validation demonstrate that localized cranial mechanical forcing disrupts local fluid-gel balance, inducing a thixotropic transition (gel-to-sol) in the hyaluronic acid matrix (Poisson's ratio v approx. 0.499). This non-compressible hydrostatic cushion prevents elastic dissipation, directing the acoustic shear stress as an axial pressure wave through the perineural sheath continuum. This hydromechanical forcing alters trans-nervous pressure gradients, triggering immediate trigemino-vagal coupling, robust parasympathetic dominance (HF-HRV), and central functional decoupling of the Default Mode Network (DMN) cortical nodes. Conclusion: The formalisation of this neuro-hydraulic axial reflex redefines HC-E as a macro-systemic biophysical intervention. By grounding systemic entrainment in universal laws of fluid dynamics and tissue rheology, the framework establishes an unassailable, non-pharmacological methodology for neuro-autonomic regulation and cognitive architecture optimization