ABSTRACT
In cortical neural circuits, the biophysics of neurons and synapses and the collective network dynamics produce spatiotemporal spike patterns that presumably are optimized for the functional specialization of the system, be it sensory, motor or memory. Therefore, different systems might use different codes. For example, the ‘spike timing code’ or ‘correlation code’ that relies on precise spike timing is critical for the computation of coincidence detection in the brainstem auditory pathways, and may also contribute to information processing in other neural systems. A ‘burst code’ is prevalent in central pattern generators of the motor systems, where rhythmicity is produced by oscillatory repetition of brief clusters of spikes (bursts). Neurons can also signal information using a ‘rate code’, by virtue of the frequency at which the spikes are discharged. The idea of rate coding originated from the work of [3], who discovered that a stimulus feature (such as intensity) could be accurately read out from the firing rate of a sensory neuron. Since then, many studies have shown that firing rates convey a large amount of stimulus-related information in neurons.
