Concept
Temporal coding
Carrying information in when spikes happen, not only in how many — the question a rate code leaves open, and the reason an event-driven circuit timestamps what a clocked one samples.
From the EE side
From the neuro side
A rate code gives up timing to make counting reliable; a timing code keeps it and asks the receiver to be precise. Nervous systems use both, and so do engineered ones — each where the trade pays.
Nearby concepts
All topics under Temporal coding
- Event cameras 2008 Image sensors whose pixels each report a change in log intensity the moment it happens, with a microsecond timestamp — the retina's transient pathway in silicon, in place of frames.
- Spike-timing-dependent plasticity 1997 A synapse strengthens when its input arrives up to a few tens of milliseconds before the cell fires and weakens when the order reverses — Hebb's rule, with spike order setting the sign.
- The Reichardt motion detector 1956 Delay one receptor's signal, multiply it by its neighbour's and subtract the mirror image: a motion detector inferred from a beetle's turning in 1956, since built in silicon and found in the fly.
- Rate coding 1926 A sensory nerve fibre signals how strong a stimulus is by how often it fires identical impulses, not by their size — seen in 1926, once valve amplifiers could record one fibre.
- The integrate-and-fire neuron 1907 A neuron reduced to a leaky capacitor that fires and resets at a threshold — Lapicque's 1907 circuit for nerve excitation, made a spiking model in the 1960s and now built into neuromorphic chips.