cs.NEMar 28, 2026

Persistent Memory Through Triple-Loop Consolidation Under Stochastic Unit Turnover

Authors: Jianwei Lou

Organizations: RailMind Systems, Neuss, Germany

Abstract

Dissipative cognitive architectures maintain computation through continuous energy expenditure, where units that exhaust their energy are stochastically replaced with fresh random state. This creates a fundamental challenge: how can persistent, context-specific memory survive when all learnable state is periodically destroyed? Existing memory mechanisms -- including elastic weight consolidation, synaptic intelligence, and surprise-driven gating -- rely on gradient computation and are inapplicable to systems that do not perform it. We introduce Deep Memory (DM), a backpropagation-free persistent memory mechanism operating through a triple-loop consolidation cycle: (1) recording of expert-specific content centroids, (2) seeding of replaced units with stored representations, and (3) stabilization through continuous re-entry. Discrete expert routing via Mixture-of-Experts (MoE) gating is required, in the regimes tested, to prevent the centroid convergence that would render stored memories identical. We derive a Foster-Lyapunov drift bound for the full triple loop, showing that seeding rescales the turnover noise floor. Across 1,0071{,}007 simulation runs over thirteen blocks: (i) removing stable context-expert binding removes specialization (MI=1.10\mathrm{MI}=1.10 vs. 0.0010.001; n=91n=91); (ii) DM achieves R=0.984R=0.984 vs. 0.3850.385 without memory (n=16n=16); (iii) continuous seeding reconstructs representations after interference (Rrecon=0.978R_\mathrm{recon}=0.978; one-shot fails; n=30n=30); (iv) the mechanism operates within a characterized (K,p)(K,p) envelope (n=350n=350); (v) recording ×\times seeding is the minimal critical dyad (n=40n=40); (vi) associative and reservoir baselines (Hopfield, ESN) are compared under matched turnover (n=370n=370). DM is thus a falsifiable, bounded mechanism for persistent memory in backpropagation-free cognitive systems, with functional parallels to hippocampal consolidation.

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