Neocortical networks of pyramidal neurons: from local locking and chaos tomacroscopic chaos and synchronization

We determine the properties of locking of inhibitory and of excitatory syna ptic connections with neocortical pyramidal cells. We are able to give an o verview of the emerging periodic behaviour, as a function of the perturbati on strength. We show that a chaotic response emerges for inhibitory connect ions on an open set of positive measure of the parameter space. This implie s that synchronization on the set of inhibitory connections is possible, wi th positive probability.