FIGURE 1.

Examples of temporal codes. (A) Schematic representation of rate and temporal codes. Each vertical bar represents a single action potential. Top row: an example of temporal coding by three neurons. Note that there is no difference in action potential numbers between left and right blue boxes for all three neurons but on the right action potentials are aligned in time between the first and the third neuron while in the second neuron action potentials are delayed and fired after a constant time interval. Such an alignment in time (coincidence) or a constant time delay can be detected by neurons. Bottom row: an example of rate coding. No neuron fires action potentials in synchrony with other neurons, only the number of action potentials is increased. (B) Simulated trains of action potentials of the same mean firing frequency but different variance and randomness. Potentially, all these action potential patterns can represent different temporal codes. Adapted with permission from Kostal et al. (2007).