Coherency detection and response segregation by synchronizing and desynchronizing delay connections in a neuronal oscillator model

Nonlinear units with delayed coupling are used as a representation of elementary neuronal oscillators. These basic elements are then coupled through delay connections to form an oscillatory network. Two classes of synchronizing and desynchronizing coupling connections within networks of oscillatory units are studied. With these types of connections, stimulus coherency leads to synchronization of the activated neuronal oscillators. A contiguous stimulus is shown to be coded by an assembly of oscillators active with zero phase lag, as required by experimental data. Furthermore, activities resulting from different stimuli lead to the formation of distinct oscillating assemblies. Two different, but overlapping, stimuli become represented by two different, coherently oscillating cell assemblies whose repetitive activities are no longer synchronized. This again agrees well with experimental observations