SOEN Learning Trail / spiking nonlinearity
SOEN Soma: Threshold and Refractory Feedback
Dendritic signal crosses a threshold, emits a spike, and recovers through a refractory loop.
An interactive model of a superconducting optoelectronic soma. Dendritic input fills a leaky collection loop whose signal s integrates upward; when the net signal s minus the refractory variable r crosses the firing threshold, the soma emits a spike (a burst of photons) and dumps flux into a refractory loop, raising r. The refractory signal subtracts from the soma and decays at its own rate, suppressing rapid re-firing. A scrolling plot shows input, the soma signal against the threshold line, refractory level, and spike ticks; chips report the live firing rate.
Soma integrates input into signal s. When net (s − r) crosses the dashed threshold, it fires and charges the refractory loop r, which subtracts from s and decays — blocking the next spike until it relaxes.
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Soma signal s
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Refractory r
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Firing rate
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