cs.LGNov 3, 2025

Online Continual Learning on Intel Loihi 2 via a Co-designed Spiking Neural Network

Authors: Elvin Hajizada, Danielle Rager, Timothy Shea, Leobardo Campos-Macias, Andreas Wild, Eyke Hüllermeier, Yulia Sandamirskaya, Mike Davies

Organizations: Institute of Informatics, University of Munich (LMU), Munich, Germany · Intel Labs, Intel Corporation, Santa Clara, CA, USA · Southwest Research Institute, San Antonio, TX, USA · Munich Center for Machine Learning (MCML) · 

Abstract

Edge AI must adapt to new classes and shifting data within a tight power budget, but online continual learning (learning from each sample before the next arrives) is where conventional processors are least efficient: each small update pays a full dispatch at full power. We present CLP-SNN, a spiking architecture that recasts the Continually Learning Prototypes (CLP) algorithm as event-driven neural dynamics: a self-normalizing local rule replaces CLP's global renormalization, prototype allocation becomes novelty-triggered neurogenesis, and correctness-modulated plasticity becomes reward-gated per-neuron metaplasticity. Deployed on Intel Loihi 2 as the first online continual learner on that chip, rehearsal-free CLP-SNN matches Replay and SLDA on OpenLORIS at 1-shot; at 25-shot, it stays within 0.8 percentage points of Replay and 6.2 points below covariance-based SLDA. Each prediction-and-update step on extracted features completes on-chip in 0.33 ms at 0.05 mJ, 7.3x lower latency and 341x lower energy than Replay on a Jetson Orin Nano.

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