Engineering polarization: How contradictory stimulation systematically undermines political moderation

Political moderation, a key attractor in democratic systems, proves highly fragile under realistic information conditions. We develop a stochastic model of opinion dynamics to analyze how noise and differential susceptibility reshape the political spectrum. Extending Marvel et al.'s deterministic framework, we incorporate stochastic media influence $\zeta (t)$ and neuropolitically-grounded sensitivity differences (${\sigma }_y>{\sigma }_x$). Analysis reveals the moderate population – stable in deterministic models – undergoes catastrophic collapse under stochastic forcing. This occurs through an effective deradicalization asymmetry ($u_B^{\text{eff}}=u+{\sigma }_y^2\mathrm{/}2>u_A^{\text{eff}}$) that drives conservatives to extinction, eliminating cross-cutting interactions that sustain moderates. The system exhibits a phase transition from multi-stable coexistence to liberal dominance, demonstrating how information flow architecture – independent of content – systematically dismantles the political center. Our findings reveal moderation as an emergent property highly vulnerable to stochastic perturbations in complex social systems.