  The detection of neuronal communities is addressed with basis on two
important concepts from neuroscience: facilitation of neuronal firing and
nearly simultaneous beginning of activation of sets of neurons. More
specifically, integrate-and-fire complex neuronal networks are activated at
each of their nodes, and the dissemination of activation is monitored. As the
activation received by each neuron accumulates, its firing gets facilitated.
The time it takes for each neuron, other than the source, to receive the first
non-zero input (beginning activation time) and the time for it to produce the
first spike (beginning spiking time) are identified through simulations. It is
shown, with respect to two synthetic and a real-world (\emph{C. elegans})
neuronal complex networks, that the patterns of beginning activation times (and
to a lesser extent also of the spiking times) tend to cluster into groups
corresponding to communities of neurons in the original complex neuronal
network. Such an effect is identified to be a direct consequence of the almost
simultaneous activation between the nodes inside the same community in which
the source of activation is placed, as well as of the respective trapping of
activation implied by the integration of activiation prior to firing.
Interestingly, the accumulation of activity and thresholds inside each neuron
were found to be essential for constraining the initial activations within each
respective community during the transient activation (no clear clusters were
observed when using overall activation or spiking rates). In addition to its
intrinsic value for neuroscience and structure-dynamics studies, these results
confirm the importance of the consideration of transient dynamics in complex
systems investigations.
