Pecten Coherence Index: A Computational Twin for Intermolt Sensory Degradation in Scorpion Pectines

This paper introduces the Pecten Coherence Index (PCI), a systems-level metric for quantifying coordinated sensory propagation across scorpion pectine networks during the intermolt aging cycle. Using a computational twin composed of coupled excitable sensory units with inhibitory gain modulation and progressive sensillar degradation, the study models how mechanosensory coherence declines between molts and partially recovers following structural renewal. The framework predicts that behavioral impairment may emerge before complete unit failure because network-level propagation coherence collapses prior to total sensillar dysfunction. Across simulated intermolt progression, PCI declines monotonically while compensatory gain modulation progressively saturates, producing a modeled transition from coordinated substrate discrimination to fragmented sensory behavior. The paper provides a falsifiable computational framework linking sensory aging, propagation coherence, inhibitory compensation, and behavioral degradation in a tractable biological system. No universal claims are made; the work is intended as a measurable and experimentally testable systems-neuroscience hypothesis.