Timing
There are two general types of neuron and synapse in Simbrain, those based on numerical integration of a differential equation, and those based on simple iteration of an algorithm. We call these "continuous" and "discrete" neurons, respectively.
Neurons that are continuous have a time-step field. The time step is a global variable that is used whenever differential equations are numerically integrated. When a continuous neuron or synapse is used, an iteration of the network represents an interval of time whose length equals the time-step. Generally speaking, the smaller the time-step, the more accurate the numerical integration.
If there is a single continuous neuron or synapse in a simulation, the network panel will display time in "seconds." Otherwise time is displayed in "iterations."