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bioRxiv · 10.1101/2024.05.20.594931

Decoding the amplitude and slope of continuous signals into spikes with a spiking point neuron model

Abstract

Scalable and efficient neural models with biological plausibility are crucial for real-time applications in neuromorphic hardware and robotics. While biophysically detailed compartmental models are valuable for their accuracy, their complexity and computational cost limit real-world application on currently available hardware. In this study, we harness the signal processing potential of the Izhikevich point neuron model to decode slope and amplitude, both important dynamical features of sensory signals. Results demonstrate that our slope-detector effectively signals up-stokes of naturalistic input signals across a wide range of frequencies. It exhibits bidirectional slope detection, with burst duration encoding slope magnitude in a graded manner. We compare to a biophysically detailed two-compartment pyramidal neuron model, showing that our bursting slope-detector performs similarly. We then demonstrate that our slope-detector does not need to burst, improving efficiency and producing more precise, discrete output by signalling events with single spikes. This makes it well-suited for real-time robotics control systems or neuromorphic hardware applications, offering greater efficiency and enabling large-scale simulations using the same computational power.

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Miko, R., Scheunemann, M., Steuber, V., Schmuker, M.. 2024-05-20. Decoding the amplitude and slope of continuous signals into spikes with a spiking point neuron model. https://doi.org/10.1101/2024.05.20.594931

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