Intrinsic Numerical Robustness and Fault Tolerance in a Neuromorphic Algorithm for Scientific Computing

As neuromorphic systems scale to thousands of near-memory cores, aging-induced permanent faults in neuron-update datapaths become an important obstacle to long-term deployment. Existing online recovery methods typically retire a faulty core and migrate its neurons, along with their weights and membrane states, to healthy cores. This whole-core treatment incurs high recovery traffic and makes recovery depend on scarce destinations; at high utilization, there may be enough surviving compute capacity but insufficient free storage to copy the affected neuron context. This paper presents SpikeRelay, an online recovery framework for diagnosed compute-unit faults. SpikeRelay exploits the fact that, in many neuromorphic cores, the compute datapath, local SRAM, and router are distinct modules: a compute fault need not destroy stored weights and states or disconnect the core from the NoC. Instead of retiring a faulty core and migrating its neuron data, SpikeRelay converts the faulty core into a storage-and-forwarding node while offloading neuron-update computation to a healthy rescue core. This decoupling of storage and computation eliminates recovery-time data migration and greatly reduces spare-SRAM requirements. Consequently, SpikeRelay sustains 100% recovery at 92.2% SRAM utilization and a 50% fault rate, whereas the best baseline achieves only 22.1%.

Biological neural systems achieve remarkable robustness and adaptability in uncertain environments through sparse, event-driven spike-based information processing and adaptive regulation. Inspired by this paradigm, this paper develops a neuromorhpic disturbance observer (NDO) and control framework that replaces conventional continuous-time signal representations with spike-timing encoding. Both disturbance estimates and control inputs are constructed via integrate-and-fire (IF) neuron dynamics from discrete spike events, yielding intrinsically event-driven updates. An adaptive-threshold triggering mechanism is inspired by spike-frequency adaptation (SFA), enabling history-dependent regulation of spike generation. Simulation results demonstrate that the proposed framework achieves neurally inspired robustness and adaptability, while the adaptive-threshold spiking scheme reduces spike events to 42.6% of the fixed-threshold case under noisy conditions.

Biological neural circuits contain specialized substructures that support distinct computational functions, yet many bio-inspired neural networks borrow biological motifs without identifying their circuit-level origins. In this study, we investigate whether zebrafish tectal microcircuits can be attributed along two computational axes: energy-efficient information processing and robustness-preserving stabilization. We reconstruct a directed zebrafish-inspired retinotectal microcircuit graph and verify retinotectal signal propagation through dynamic simulation. A leaky integrate-and-fire spiking neural network is then used as a nonlinear perturbation testbed, where predefined subcircuits are selectively ablated and evaluated using the Energy Sensitivity Index and the Robustness Sensitivity Index.The results reveal a functional dissociation between two tectal subcircuits.The ns_TIN subcircuit shows a low spike footprint but a measurable influence on prediction error, suggesting a role as a spike-efficient internal information gate.In contrast, the superficial_TIN subcircuit produces the highest robustness sensitivity, suggesting a feedback-like role in maintaining system-level stability.We further transfer these attributed functions into ResNet18-based artificial neural networks and evaluate them on CIFAR-10 under inference-budget reduction and Gaussian noise corruption. The ns_TIN-inspired module improves performance preservation under reduced computation, whereas the superficial_TIN-inspired module improves robustness under input noise. These findings provide a subcircuit-level route for linking biological circuit organization with bio-inspired neural architecture design.