  We report the emergent dynamics of a community structured modular network of
chaotic Hindmarsh-Rose (HR) neurons with inhibitory synapses. We find the
inhibitory coupling between the neuronal modules lead to complete
synchronization of neurons in a module, and also pushes modules into
interesting sequences of travelling burst patterns. When dynamical time-scales
vary for neurons in different modules, hence breaking the symmetry among them,
we see specific sequences of travelling burst patterns that are characteristic
of the time-scale mismatch and coupling strengths. Thus for a modular network
with two time-scales, the neuronal communities enter into synchronized
frequency locked clusters with the bursting sequences having recurring
patterns. Our study provides a complete characterization of the spatio-temporal
regularity in terms of frequency locking for temporal order and burst sequence
patterns for spatial order in the collective dynamics of the neuronal clusters.
Our results have significance in the process of information coding in terms of
frequency of firing dynamics among neurons and in selective communication based
on the sequences of bursts.
